Programming Language C Tutorial Introduction 主講人：虞台文.

Programming Language CTutorial Introduction

主講人：虞台文

Content Background Getting Started IDE (Integrated Development Environment) Main Parts of C Programs Variables and Arithmetic Expressions The for statement Symbolic Constants Character Input and Output Arrays Functions Character Arrays External Variables and Scope


Background

Textbooks

1. C How to Program, 5th Edition, by Harvey M. Deitel , Paul J. Deitel.

2. The C programming Language, 2nd Editon, by Brian W. Kernighan and Dennis M. Ritchie, Prentice-Hall in 1988.

Grading

1. Homework 40%

2. Midterm 30%

3. Final 30%

4. Other 10%

The C Language

Currently, the most commonly-used language for embedded systems– High-level assembly

Very portable– compilers exist for virtually every processor

Easy-to-understand compilation Produces efficient code Fairly concise

C History

Developed between 1969 and 1973 along with Unix

Due mostly to Dennis Ritchie

Designed for systems programming– Operating systems

– Utility programs

– Compilers

– Filters

Evolved from B, which evolved from BCPL

The Development of the C Language

Computer Architecture

ALUALU

ControlControl

CPU

InputInput OutputOutput

MemoryMemory

InputDevice

OutputDevice


Getting Started

Setting Program Development Environment






%SystemRoot%\system32\cmd.exe/K "F:\VS6\VC98\Bin\VCVARS32.BAT"

%SystemRoot%\system32\cmd.exe/K "F:\VS6\VC98\Bin\VCVARS32.BAT"


Our First C Program Hello World


#include <stdio.h>

main(){

printf("hello, world\n");}

#include <stdio.h>

main(){



#include <stdio.h>

main(){


#include <stdio.h>

main(){


include information about standard

library

include information about standard

library

define a function called mainthat received no argument

values


values


#include <stdio.h>

main(){


#include <stdio.h>

main(){



values


values


#include <stdio.h>

main(){


#include <stdio.h>

main(){


statements of main are enclosed in

braces

statements of main are enclosed in

braces


#include <stdio.h>

main(){


#include <stdio.h>

main(){


main calls library function printf

main calls library function printf


Compiling and Linking






Execution

Execution

Exercises

1. Create some typo errors for Hello.c, and redo the compiling/linking process. Watch and understand the screen output reported by cl.

2. Add more printf statements in Hello.c and redo the compiling/linking/execution process.


IDE

Visual C++ 6.0

Visual C++ 6.0

Visual C++ 6.0

Win32 Console Application



Hello_IDE

Hello_IDE

Hello_IDE

Hello_IDE

Hello_IDE

Hello_IDE

Hello.c

Building Application

Building Application

Execution

Execution

Files Generated by IDE


Main Parts of C Programs

Main Parts

Headers/Comments/Expressions

#include <stdio.h>

/* Our first C Program */

main(){


#include <stdio.h>

/* Our first C Program */

main(){


Example Identify the three parts in the following program

Remark C++ also uses // to comment a single line.

The Syntax of C Language


Variables and Arithmetic Expressions

Example:Fahrenheit-Celsius table

59 ( 32)C F

Example:Fahrenheit-Celsius Table

59 ( 32)C F

#include <stdio.h>/* print Fahrenheit-Celsius table for fahr = 0, 20, ..., 300 */main(){

int fahr, celsius;int lower, upper, step;lower = 0; /* lower limit of temperature scale */upper = 300; /* upper limit */step = 20; /* step size */fahr = lower;while (fahr <= upper) {

celsius = 5 * (fahr-32) / 9;printf("%d\t%d\n", fahr, celsius);fahr = fahr + step;

}}




}}


59 ( 32)C F




}}




}}

Statements59 ( 32)C F




}}




}}

Individual statements are terminated by semicolons.

Individual statements are terminated by semicolons.

Variable Declarations




}}




}}

In C, all variables must be declared before they are used.

– Usually declared at the beginning of the function before any executable statements.

A declaration announces the properties of variables; it consists of a name and a list of variables.

In C, all variables must be declared before they are used.

– Usually declared at the beginning of the function before any executable statements.

A declaration announces the properties of variables; it consists of a name and a list of variables.

59 ( 32)C F

Variable Declarations




}}




}}

59 ( 32)C F

• The integer data type.• What is its range?

• The integer data type.• What is its range?

Integer

The range of integer depends on

machine

– 16-bit machine

32768 +32767

– 32-bit machine

2147483646 +2147483647

int fahr, celsius;int lower, upper, step;


Integer


machineINT_MIN INT_MAX



Integer


machineINT_MIN INT_MAX



Float

A float number is typically a 32-bit quantity, with at least six significant digits and magnitude generally between about 10-38 and 1038

float fahr, celsius;float lower, upper, step;

float fahr, celsius;float lower, upper, step;

FLT_MIN FLT_MAX

Fundamental Types

Type Size

char 1 byte

short 2 bytes

int 4 bytes

long 4 bytes

float 4 bytes

double 8 bytes

Machine Dependent

Type Size

char 1 byte

short 2 bytes

int 4 bytes

long 4 bytes

float 4 bytes

double 8 bytes

Type Size

char 1 byte

short 2 bytes

int 4 bytes

long 4 bytes

float 4 bytes

double 8 bytes

Fundamental Types in Microsoft C++

Assignment Statements




}}




}}

Assign a value computed from an expression to a variable.

While Loop




}}




}}

The body of a while loop is repeatedly executed as long as the condition expression is tested true.

The body of a while loop is repeatedly executed as long as the condition expression is tested true.

while( cond_expression )statement

Arithmetical Operations




}}




}}

59 ( 32)C F

Can it be “celsius = 5/9*(fahr-32);

”?Why?

Can it be “celsius = 5/9*(fahr-32);

”?Why?

printf General-Purpose Output Formatting Function




}}




}}


printf("%d\t%d\n", fahr, celsius);

format string

decimal tab decimal newline





}}




}}

Left alignedLeft aligned


Synopsis

#include <stdio.h>int printf(const char *format, ...);

Description

printf writes to the standard output stream using putchar, under control of the string pointed to by format that specifies how subsequent arguments are converted for output.

If there are insufficient arguments for the format, the behavior is undefined. If the format is exhausted while arguments remain, the excess arguments are evaluated but are otherwise ignored.

printf returns number of characters transmitted, or a negative value if an output or encoding error occurred.

Synopsis

#include <stdio.h>int printf(const char *format, ...);

Description

printf writes to the standard output stream using putchar, under control of the string pointed to by format that specifies how subsequent arguments are converted for output.

If there are insufficient arguments for the format, the behavior is undefined. If the format is exhausted while arguments remain, the excess arguments are evaluated but are otherwise ignored.

printf returns number of characters transmitted, or a negative value if an output or encoding error occurred.




celsius = 5 * (fahr-32) / 9;printf("%3d %6d\n", fahr, celsius);fahr = fahr + step;

}}



celsius = 5 * (fahr-32) / 9;printf("%3d %6d\n", fahr, celsius);fahr = fahr + step;

}}

Right alignedRight aligned

Example:Fahrenheit-Celsius Table (Float)

59 ( 32)C F


float fahr, celsius;float lower, upper, step;lower = 0; /* lower limit of temperature scale */upper = 300; /* upper limit */step = 20; /* step size */fahr = lower;while (fahr <= upper) {

celsius = (5.0/9.0) * (fahr-32.0);printf("%3.0f %6.1f\n", fahr, celsius);fahr = fahr + step;

}}




}}

Example:Fahrenheit-Celsius Table (Float)

59 ( 32)C F




}}




}}

More on printf

Statements

Simple Statementslower = 0;

upper = 300;

step = 20;

fahr = lower;

Null Statement; // a null statement

Compound Statements{


}

4 simple statements

1 compound statement

While Statements

while( cond_expression )

statement

The statement can be:

a simple statement

a null statement

a compound statements

Program Indentation




}}




}}

Program Indentation




}}




}}

StatementStatementStatementStatementStatementStatement

Statement

Program Indentation




}}




}}


StatementStatementStatement

Program Indentation




}}




}}


Compound Statement


The for Statement


59 ( 32)C F




}}




}}

There are many ways to do the same task.


59 ( 32)C F

#include <stdio.h>

/* print Fahrenheit-Celsius table */

main()

{

int fahr;

for (fahr = 0; fahr <= 300; fahr = fahr + 20)

printf("%3d %6.1f\n", fahr, (5.0/9.0)*(fahr-

32));

}

#include <stdio.h>


main()

{

int fahr;



32));

}

The for Statement

#include <stdio.h>


main()

{

int fahr;



32));

}

#include <stdio.h>


main()

{

int fahr;



32));

}

for ( init-exp ; cond-exp ; loop-exp )statement

for ( init-exp ; cond-exp ; loop-exp )statement

for vs. while

The choice between while and for is arbitrary, based on which seems clearer.

The for is usually appropriate for loops

in which the initialization and increment are single statements and logically related.

Exercises3. Modify the temperature conversion program to print

the table in reverse order, that is, from 300 degrees to 0.

Exercises4. Using only the techniques you learned, write a

program that calculates the squares and cubes of the number from 0 to 10 and used tabs to print the following table of values.

number square cube0 0 01 1 12 4 83 9 274 16 645 25 1256 36 2167 49 3438 64 5129 81 71910 100 1000


Symbolic Constants

#define Text Substitution

#define name replacement list

#define PI 3.1415926

Example:


#include <stdio.h>

#define LOWER 0 /* lower limit of table */

#define UPPER 300 /* upper limit */

#define STEP 20 /* step size */


main()

{

int fahr;

for (fahr = LOWER; fahr <= UPPER; fahr = fahr +

STEP)


32));

}

#include <stdio.h>

#define LOWER 0 /* lower limit of table */

#define UPPER 300 /* upper limit */

#define STEP 20 /* step size */


main()

{

int fahr;

for (fahr = LOWER; fahr <= UPPER; fahr = fahr +

STEP)


32));

}


Character Input and Output

getchar() & putchar()

Synopsis#include <stdio.h>int getchar(void);

Descriptiongetchar reads a single character from the standard input stream.If the stream is at end-of-file or a read error occurs, getchar returns EOF.

Synopsis#include <stdio.h>int getchar(void);

Descriptiongetchar reads a single character from the standard input stream.If the stream is at end-of-file or a read error occurs, getchar returns EOF.

Synopsis#include <stdio.h>int putchar(int c);

Descriptionputchar writes the character c to the standard output stream. putchar returns the character written. If a write error occurs, putchar returns EOF.

Synopsis#include <stdio.h>int putchar(int c);

Descriptionputchar writes the character c to the standard output stream. putchar returns the character written. If a write error occurs, putchar returns EOF.

#define EOF (-1)

Example: Typewriter (Version 1)

#include <stdio.h>/* copy input to output; 1st version */

main(){ int c; c = getchar(); while (c != EOF) {

putchar(c); c = getchar();

}}


main(){ int c; c = getchar(); while (c != EOF) {

putchar(c); c = getchar();

}}

!= not equal



main(){

int c;c = getchar();while ((c = getchar()) != EOF)

putchar(c);}


main(){

int c;c = getchar();while ((c = getchar()) != EOF)

putchar(c);}

The return value of an assignment statement is value of the variable after the assignment.

simple stateme

nt



main(){

int c;c = getchar();while ((c = getchar()) != EOF) putchar(c);

}


main(){

int c;c = getchar();while ((c = getchar()) != EOF) putchar(c);

}

The return value of an assignment statement is value of the variable after the assignment.

Example: Character Counting (Version 1)

#include <stdio.h>/* count characters in input; 1st version */

main(){

long nc;nc = 0;while (getchar() != EOF)

++nc;printf("%ld\n", nc);

}

#include <stdio.h>/* count characters in input; 1st version */

main(){

long nc;nc = 0;while (getchar() != EOF)

++nc;printf("%ld\n", nc);

}

++ increment

simple stateme

nt


#include <stdio.h>

/* count characters in input; 1st version */

main()

{

long nc;

nc = 0;

while (getchar() != EOF) ++nc;

printf("%ld\n", nc);

}

#include <stdio.h>

/* count characters in input; 1st version */

main()

{

long nc;

nc = 0;

while (getchar() != EOF) ++nc;

printf("%ld\n", nc);

}

++ increment


#include <stdio.h>

/* count characters in input; 2nd version */

main(){ double nc;

for (nc = 0; getchar() != EOF; ++nc) ; printf("%.0f\n", nc);}

#include <stdio.h>


main(){ double nc;

for (nc = 0; getchar() != EOF; ++nc) ; printf("%.0f\n", nc);}

null stateme

nt


#include <stdio.h>


main()

{

double nc;

for (nc = 0; getchar() != EOF; ++nc);

printf("%.0f\n", nc);

}

#include <stdio.h>


main()

{

double nc;

for (nc = 0; getchar() != EOF; ++nc);

printf("%.0f\n", nc);

}

Example: Line Counting

#include <stdio.h>

/* count lines in input */main(){ int c, nl;

nl = 0; while ((c = getchar()) != EOF) if (c == '\n') ++nl; printf("%d\n", nl);}

#include <stdio.h>



== equals to

if ( expression ) statement

if ( expression ) statement else statement

if ( expression ) statement

if ( expression ) statement else statement

simple stateme

nt


#include <stdio.h>



#include <stdio.h>



simple stateme

nt


#include <stdio.h>



#include <stdio.h>



simple stateme

nt

Can we move to here?

Example: Word Counting

OUT IN

visible

non-visible

visible

>

non-visible

This is a test case.OIIIIOIIOIOOOIIIIO OIIIII

Example: Word Counting

#include <stdio.h>#define IN 1 /* inside a word */#define OUT 0 /* outside a word *//* count lines, words, and characters in input */main(){ int c, nl, nw, nc, state; state = OUT; nl = nw = nc = 0; while ((c = getchar()) != EOF) {

++nc;if (c == '\n') ++nl;if (c == ' ' || c == '\n' || c = '\t') state = OUT;

else if (state == OUT) { state = IN; ++nw;}

} printf("%d %d %d\n", nl, nw, nc);}

#include <stdio.h>#define IN 1 /* inside a word */#define OUT 0 /* outside a word *//* count lines, words, and characters in input */main(){ int c, nl, nw, nc, state; state = OUT; nl = nw = nc = 0; while ((c = getchar()) != EOF) {

++nc;if (c == '\n') ++nl;if (c == ' ' || c == '\n' || c = '\t') state = OUT;

else if (state == OUT) { state = IN; ++nw;}

} printf("%d %d %d\n", nl, nw, nc);}

OUT INvisible

non-visible

visible

>non-visible

Exercises

7. Write a program to print a histogram of the frequencies of different characters in its input.


Arrays

Arrays

Array is a data structure that stores contiguous data elements of the same type.

Examples:int score[50];char address[50];double distance[50];

score

address

distance

200

byte

s50

byte

s400

byte

s

ArraysExamples:int score[50];char address[50];double distance[50];

score

address

distance

...

score[0]

score[1]

score[49]


score

address

distance

address[0]address[1]address[2]

address[49]

...


score

address

distance ...

distance[0]

distance[49]

#include <stdio.h>

/* count digits, white space, others */main(){

int c, i, nwhite, nother;int ndigit[10];

nwhite = nother = 0;for (i = 0; i < 10; ++i) ndigit[i] = 0;

while ((c = getchar()) != EOF)if (c >= '0' && c <= '9') ++ndigit[c-'0'];else if (c == ' ' || c == '\n' || c == '\t') ++nwhite;else ++nother;

printf("digits =");for (i = 0; i < 10; ++i) printf(" %d", ndigit[i]);printf(", white space = %d, other = %d\n", nwhite, nother);

}

#include <stdio.h>






}

Example: Digit Counting

&& logical and operator|| logical or operator

#include <stdio.h>






}

#include <stdio.h>






}


#include <stdio.h>






}

#include <stdio.h>






}


#include <stdio.h>






}

#include <stdio.h>






}


if Statement

if (condition1)statement1

else if (condition2) statement2


...else

statementn

if (condition1)statement1



...else

statementn

The dangling else problem

Exercises

5. Write a program that prints its input one word per line.

6. Write a program that prints only a single white character between words.

Exercises

7. Write a program to print a histogram of the frequencies of different characters in its input.


Functions

Functions we have used

printf

getchar

putchar

Functions

A way to encapsulate some computation.

Similar to a subroutine or function in Fortran, or a procedure or function in Pascal.

A properly designed function allow us to– know what is done, but

– ignore how a job is done

Function Definition

return-type function-name(parameter declarations, if an

y)

{

declarations

statements

}


y)

{

declarations

statements

}

Function Definition


y)

{

declarations

statements

}


y)

{

declarations

statements

}

If absent, return type is considered int.

If absent, return type is considered int.

Called formal

parameters

Called formal

parameters

Example: Power#include <stdio.h>int power(int m, int n);/* test power function */main(){ int i;

for (i = 0; i < 10; ++i) printf("%d %d %d\n", i, power(2,i), power(-3,i)); return 0;}

/* power: raise base to n-th power; n >= 0 */int power(int base, int n){ int i, p;

p = 1; for (i = 1; i <= n; ++i) p = p * base; return p;}

#include <stdio.h>int power(int m, int n);/* test power function */main(){ int i;




forward reference

Example: Power#include <stdio.h>int power(int m, int n);/* test power function */main(){ int i;




#include <stdio.h>int power(int m, int n);/* test power function */main(){ int i;




Example: Power (Version 2)





/* power: raise base to n-th power; n >= 0; version 2 */

int power(int base, int n){ int i, p;

for (p = 1; n < 0; --n) p = p * base; return p;}




Example: Power (Version 2)







. . . . . . . . . .main(){ int n, val;

n = 5; val = power(2, n); printf("val=%d n=%d %d\n", val, n);}. . . . . . . . . .

. . . . . . . . . .main(){ int n, val;

n = 5; val = power(2, n); printf("val=%d n=%d %d\n", val, n);}. . . . . . . . . .

n=?n=?

Call by Value

In C, all function arguments are passed “by value.”

– the called function is given the values of its arguments in

temporary variables rather than the originals.

– Modifying the values of formal parameters doesn’t effect

the value of originals

How about if a function has arrays as its

parameters?


Character Arrays

Strings in C Null-terminated string In C, a string is stored as an array

of characters containing the characters in the string and terminated with a '\0' to mark the end.

char str[]="hello\n";

Example: h (68)

e (65)

l (6C)

l (6C)

o (6F)

\n (0A)

\0 (00)

str

Strings in C

Example: Print the Longest Line

while (there's another line)

if (it's longer than the previous longest)

(save it)

(save its length)

print longest line



(save it)

(save its length)

print longest line




(save it)

(save its length)

print longest line



(save it)

(save its length)

print longest line

Implement a getline() function which returns the length of the line read.

Implement a getline() function which returns the length of the line read.

Implement a copy() function to save string.

Implement a copy() function to save string.


/* getline: read a line into s, return length */int getline(char s[],int lim){ int c, i;

for (i=0; i < lim-1 && (c=getchar())!=EOF && c!='\n'; ++i)s[i] = c;

if (c == '\n') { s[i] = c; ++i; } s[i] = '\0'; return i;}




&& logical and operator









Simplification

s[i++] = c;

s[i++] = c;


/* getline: read a line into s, return length *//* simplified version */int getline(char s[],int lim){ int c, i;

for (i=0; i < lim-1 && (c=getchar())!=EOF && c!='\n';) s[i++] = c; if (c == '\n') s[i++] = c; s[i] = '\0'; return i;}





/* copy: copy 'from' into 'to'; assume to is big enough */

void copy(char to[], char from[])

{

int i;

i = 0;

while ((to[i] = from[i]) != '\0') ++i;

}



{

int i;

i = 0;

while ((to[i] = from[i]) != '\0') ++i;

}


#include <stdio.h>#define MAXLINE 1000 /* maximum input line length */

int getline(char line[], int maxline);void copy(char to[], char from[]);

/* print the longest input line */main(){

int len; /* current line length */int max; /* maximum length seen so far */char line[MAXLINE]; /* current input line */char longest[MAXLINE]; /* longest line saved here */

max = 0;while ((len = getline(line, MAXLINE)) > 0)

if (len > max) {max = len;copy(longest, line);

}if (max > 0) /* there was a line */

printf("%s", longest);return 0;

}. . . . . . . . . . . .



/* print the longest input line */main(){

int len; /* current line length */int max; /* maximum length seen so far */char line[MAXLINE]; /* current input line */char longest[MAXLINE]; /* longest line saved here */

max = 0;while ((len = getline(line, MAXLINE)) > 0)

if (len > max) {max = len;copy(longest, line);

}if (max > 0) /* there was a line */

printf("%s", longest);return 0;

}. . . . . . . . . . . .




Exercises

8. Write a function getlinestr() by modifying getline() described above so that the string read doesn’t include '\n'.

9. Write a function reverse(char s[]) that reverses the character string s.

10. Write a function int strlen(char s[]) that returns the number of characters in string s.

11. Write a program to demonstrate that the about three functions you wrote are correct.

Exercises

12. Write a function int atoi(char s[]) that converts a signed decimal numeric string, assumed the syntax is correct, to an integer, and write a program to verify the correctness of your program.

13. Write a program that reads two integers from the standard input stream and output their minimum and maximum to the standard output stream. You can’t use library function scanf() to read data.

14. (Take home) Write a function void itoa(int n, char s[]) that converts a signed integer to a signed decimal numeric string, and write a program to verify the correctness of your program.


External Variables and Scope

Local (Private) Variables



/* print the longest input line */main(){ int len; /* current line length */ int max; /* maximum length seen so far */ char line[MAXLINE]; /* current input line */ char longest[MAXLINE]; /* longest line saved here */

max = 0; while ((len = getline(line, MAXLINE)) > 0) if (len > max) { max = len;

copy(longest, line); } if (max > 0) /* there was a line */

printf("%s", longest); return 0;}











{

int i;

i = 0;

while ((to[i] = from[i]) != '\0') ++i;

}





{

int i;

i = 0;

while ((to[i] = from[i]) != '\0') ++i;

}

Local (Private) Variables

















{

int i;

i = 0;

while ((to[i] = from[i]) != '\0') ++i;

}





{

int i;

i = 0;

while ((to[i] = from[i]) != '\0') ++i;

}

Each local variable comes into existence only when the function is called, and disappears when the function is exited.

Hence, also known as automatic variables.

Each local variable comes into existence only when the function is called, and disappears when the function is exited.

Hence, also known as automatic variables.

Global (Extern) Variables

Global variables that are defined external to all functions can be accessed by name by any function.

Furthermore, they remain in existence permanently.


#include <stdio.h>

#define MAXLINE 1000 /* maximum input line size */

int max; /* maximum length seen so far */char line[MAXLINE]; /* current input line */char longest[MAXLINE]; /* longest line saved here */

int getline(void);void copy(void);

/* print longest input line; specialized version */main(){ . . . . . . . . . . . . }

/* getline: specialized version */int getline(void){ . . . . . . . . . . . . }

/* copy: specialized version */void copy(void){ . . . . . . . . . . . . }

#include <stdio.h>







defined external to all functions


#include <stdio.h>







#include <stdio.h>








/* print longest input line; specialized version */ main(){ int len; extern int max; extern char longest[];

max = 0; while ((len = getline()) > 0) if (len > max) { max = len; copy(); } if (max > 0) /* there was a line */ printf("%s", longest); return 0;}




#include <stdio.h>







#include <stdio.h>








/* getline: specialized version */int getline(void){ int c, i; extern char line[];

for (i = 0; i < MAXLINE - 1 && (c=getchar()) != EOF && c != '\n'; ++i) line[i] = c; if (c == '\n') { line[i] = c; ++i; } line[i] = '\0'; return i;}




#include <stdio.h>







#include <stdio.h>








/* copy: specialized version */void copy(void){ int i; extern char line[], longest[];

i = 0; while ((longest[i] = line[i]) != '\0') ++i;}




#include <stdio.h>







#include <stdio.h>




















The declarations for referencing external variables are redundant if they are defined in the header part of the same file .

The declarations for referencing external variables are redundant if they are defined in the header part of the same file .

Example: Print the Longest Line (Multiple Source Files) I

/* main.c */#include <stdio.h>










/* functions.c *//* getline: specialized version */int getline(void){ . . . . . . . . . . . . }




Example: Print the Longest Line (Multiple Source Files) I



























Must be kept.Must be kept.

Must be kept.Must be kept.

Example: Print the Longest Line (Multiple Source Files) II











/* functions.c */#include <stdio.h>#include "externdef.h"/* getline: specialized version */int getline(void){ . . . . . . . . . . . . }




/* externdef.h */#define MAXLINE 1000 /* maximum input line size */

extern int max; /* maximum length seen so far */extern char line[]; /* current input line */extern char longest[]; /* longest line saved here */



Example: Print the Longest Line (Multiple Source Files) II



























Exercise

15. (Take home) Write a program to remove all comments from a C program. Don't forget to handle quoted strings and character constants properly. C comments don't nest.

Programming Language C Tutorial Introduction 主講人：虞台文.

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