CSC1201: Programming Language 2 Lecture 1 Level 2 Course Nouf Aljaffan (C) 2012 - CSC 1201 Course at KSU 1
Dec 14, 2015
Nouf Aljaffan (C) 2012 - CSC 1201 Course at KSU
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CSC1201: Programming Language 2
Lecture 1
Level 2 Course
Nouf Aljaffan (C) 2012 - CSC 1201 Course at KSU
“Hello World” program#include <iostream>
using namespace std;
int main ()
{
cout << “Hello World\n”;
Return 0;
}
include information from the standard input/output library, iostream.
The instruction is more properly called a “preprocessor” instruction
The # hash character starts the line to denote a preprocessor instruction.
library name must be enclosed by < and > angled brackets.
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Nouf Aljaffan (C) 2012 - CSC 1201 Course at KSU
“Hello World” program using namespace std; The second line of the program makes all the functions within the
iostream library available for use by their standard names, which are in the namespace std. One of these is a function named cout that is used to write the output from a program.
int main () In the function declaration the data type is specified as int, meaning
integer. This means that after executing its statements this function must return an integer value to the operating system.
The braces { } contain the statements to be executed by the program.
The final statement in the main function Return a value of zero to the operating system to indicate that the program executed correctly.
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Nouf Aljaffan (C) 2012 - CSC 1201 Course at KSU
Declaring and Initializing Variables
To declare variables for example◦ int first, second;
◦ char ch;
◦ double x;
◦ bool flage;
To declare and initialize variables for example◦ int first = 13, second = 10;
◦ char ch = ‘A’;
◦ double x = 12.6;
◦ bool flage = true;
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Nouf Aljaffan (C) 2012 - CSC 1201 Course at KSU
Input (Read) Statement
The syntax of cin together with >> is:
cin >> variable >> variable >> ……….;
◦For example:
cin >> first >> second;
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Nouf Aljaffan (C) 2012 - CSC 1201 Course at KSU
OutputThe syntax of cout together with << is:
cout << expression or manipulator << expression or manipulator ……….;
The expression is evaluated and its value is printed at the current insertion point on the output device.
A manipulator is used to format the output. The simplest manipulator is endl.
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Nouf Aljaffan (C) 2012 - CSC 1201 Course at KSU
Working with String The C++ <string> class provides methods to manipulate
strings of text. This is an example of Declaring and initializing a string
variable
#include <string>#include <iostream>using namespace std;
int main(){ string str = "C++ is fun";
…………}
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Nouf Aljaffan (C) 2012 - CSC 1201 Course at KSU
Control Structures
IF statement:if (condition){ statement(s);}
IF Else statement:if (condition){ statement(s); ← True Branch}else{ statement(s); ← False Branch}
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Nouf Aljaffan (C) 2012 - CSC 1201 Course at KSU
Example : If statement#include <iostream>
using namespace std;
int main()
{
int num=2;
bool flag=0;
if( (num==2) && (flag) )
{
cout << "The first test is true\n";
}
else if( (num==2) && (!flag) )
{
cout << "The second test is true\n";
}
return 0;
}
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Nouf Aljaffan (C) 2012 - CSC 1201 Course at KSU
Example: Switch Structures#include <iostream>
using namespace std;
int main()
{
}
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char letter;
cout << "Enter any a-z character: "; cin >> letter;
switch(letter) { case 'a' :
cout << "Letter \'a\' found\n"; break;
case 'b' : cout << "Letter \'b\' found\n"; break;
case 'c' : cout << "Letter \'c\' found\n"; break;
default : cout << "Letter is not a, b or c\n"; } return 0;
Nouf Aljaffan (C) 2012 - CSC 1201 Course at KSU
While looping Structure
While (condition)
{
statement(s);
}
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Nouf Aljaffan (C) 2012 - CSC 1201 Course at KSU
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Example: While loop#include <iostream>
using namespace std;
int main()
{
int i=0;
while( i<=20 )
{
cout << i << " ";
i = i + 5 ;
}
cout << endl;
return 0;
}
output: 0 5 10 15 20
Nouf Aljaffan (C) 2012 - CSC 1201 Course at KSU
For looping Structure for (expression1; condition;
expression2) { statement(s) }
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Nouf Aljaffan (C) 2012 - CSC 1201 Course at KSU
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Example: For Loop#include <iostream>using namespace std;
int main(){int i,num;
cout<<"enter any number: ";cin>>num;for ( i=1 ; i<=10 ; i++ ){cout << endl << num << "*“ << i << "=“ << num*i << endl;}
return 0;}
Output : enter any number : 11*1=11*2=21*3=3..