Any C Program consists of the following parts: Preprocessor part Main function. This consists of the following: The declaration part The Initialization.

7. C PROGRAM STRUCTURE

1. STRUCTURE OF A C PROGRAM

Any C Program consists of the following parts:Preprocessor partMain function. This consists of the following:

The declaration part The Initialization part The Input Processing (Assignment, if/switch, calculations, or any

other C statements that will be covered later) The Output Return (0) command

This is shown in the diagram of the next slide.

Dr. Soha S. Zaghloul 2

1. STRUCTURE OF A C PROGRAM - SUMMARIZED

Preprocessor part (#include, #define)

Main function

int main (void){

Return (0);} // end of main function

// declaration part

// initialization part

// input part

// processing

// output



1.1 DECLARATION PART


Main function

int main (void){


// declaration partint number1, number2, number3;char gender;double salary;


// input part

// processing

// output


1.2 INITIALIZATION PART


Main function

int main (void){


// declaration part

// initialization parttotal = 0; // previously declareddouble product = 1.0; // undeclaredchar name[20] = “xxxxxxxxxxxxxxxx”; //undeclared// input part

// processing

// output


1.3 INPUT PART


Main function

int main (void){


// declaration part


// input partprintf (“Enter the values of three integers\n”);scanf (“%d%d%d”, &number1, &number2, &number3);// processing

// output


1.4 PROCESSING PART


Main function

int main (void){


// declaration part


// input part

// processingtotal = number1 + number2 + number3;

// output


1.4 PROCESSING PART (2)


Main function

int main (void){


// declaration part


// input part

// processingtotal = total + number1;product = product * number2;

// output


1.4 PROCESSING PART (3)Preprocessor part (#include, #define)

Main function

int main (void){


// declaration part


// input part

// processingif (total == 0) total = total + number1;else product = product * number1;

// output


1.5 OUTPUT PART


Main function

int main (void){


// declaration part


// input part

// processing

// outputprintf (“Final Results are: “);printf (“Total = %d, Product = %f”, total, product);


2. EXAMPLE (1)

Write a complete program that calculates the average of three integer numbers.

Input?

number1

number2

number3

Type?

integer

integer

integer

Output?

average

Type?

double

// declaration partint number1, number2, number3;double average;

value?

Through scanf

Through scanf

Through scanf

value?

To be calculated

// input partprintf (“Enter the values of the three integers: \n”);scanf (“%d%d%d”, &number1, &number2, &number3);


2. EXAMPLE (1) – CONT’D

Write a complete program that calculates the average of three integer numbers.

// declaration partint number1, number2, number3;double average;

// input partprintf (“Enter the values of the three integers: \n”);scanf (“%d%d%d”, &number1, &number2, &number3);

// processing partaverage = (number1 + number2 + number3) /3.0;

// output partprintf (“The average equals %f “, average);

#include <stdio.h>

int main (void){

return (0);} // end of main

2. EXAMPLE (2)

Write a complete program to select an operation based on the value of inventory. Increment total_paper by paper_order if inventory is ‘B’ or ‘C’; increment total_ribbon by ribbon_order if inventory is ‘E’, ‘F’, or ‘D’; increment total_label by label_order if inventory is ‘A’ or ‘X’. Do nothing if inventory is ‘M’. Display an error message if the value of inventory is not one of these eight letters.

input?

inventory

paper_order

ribbon_order

label_order

type?

char

integer

integer

integer

value?

Through scanf

Through scanf

Through scanf

Through scanf

// declaration partchar inventory;int paper_order, ribbon_order, label_order;





// input partprintf (“Enter inventory \n”);scanf (“%c”, inventory);

#include <stdio.h>int main (void){







// processing partswitch (inventory){ case ‘B’: case ‘C’: printf (“Enter amount of ordered paper \n”); scanf (“%d”, &paper_order);

total_paper = total_paper + paper_order; printf (“Total paper = %d”, total_paper);

break;

// iniatlization partint total_paper = 0;







// processing part// continuation of the switch statement case ‘E’: case ‘F’: case ‘D’: printf (“Enter amount of ordered ribbon \n”); scanf (“%d”, &ribbon_order);

total_ribbon = total_ribbon + paper_order; printf (“Total ribbon = %d”, total_ribbon);

break;

// iniatlization partint total_paper = 0, total_ribbon = 0;







// processing part// continuation of the switch statement case ‘A’: case ‘X’: printf (“Enter amount of ordered label \n”); scanf (“%d”, &label_order);

total_label = total_label + label_order; printf (“Total label = %d”, total_label);

break;

// iniatlization partint total_paper = 0, total_ribbon = 0, total_label = 0;







// processing part// continuation of the switch statement case ‘M’: break;

default: printf (“Invalid input \n”); //invalid inventory value break;} // end of switch statement

return (0);} //end of main

// iniatlization partint total_paper = 0, total_ribbon = 0, total_label = 0;



2. EXAMPLE (2) – CONT’D// processing part// Using if statementif (inventory == ‘B’) || (inventory == ‘C’) { printf (“Enter amount of ordered paper \n”); scanf (“%d”, &paper_order); total_paper = total_paper + paper_order; printf (“Total paper = %d”, total_paper); } // (inventory == ‘B’) || (inventory == ‘C’)else if (inventory == ‘E’) || (inventory == ‘F’) || (inventory == ‘D’) { printf (“Enter amount of ordered ribbon \n”); scanf (“%d”, &ribbon_order); total_ribbon = total_ribbon + paper_order; printf (“Total ribbon = %d”, total_ribbon); } // (inventory == ‘E’) || (inventory == ‘F’) || (inventory == ‘D’) else if (inventory == ‘A’) || (inventory == ‘X) { printf (“Enter amount of ordered label \n”); scanf (“%d”, &label_order); total_label = total_label + label_order;

printf (“Total label = %d”, total_label); } // (inventory == ‘A’) || (inventory == ‘X) else if (inventory != ‘M’) // what if (inventory == ‘M)? printf (“Invalid Input \n”)


2. EXAMPLE (3)

The table below shows the normal boiling points of several substances. Write a program that prompts the user for the observed boiling point of a substance in ºC. The program then identifies the substance if the observed boiling point is within 5% (more or less) of the expected boiling point. If the data input is more than 5% higher or lower than any of the boiling points in the table, the program should output the message “Substance unknown”.Substance Expected Boiling Point (ºC)Water 100Mercury 357Copper 1187Silver 2193Gold 2660


2. EXAMPLE (3)



2. EXAMPLE (3)Input?

observed

Type?

double

Output?

substance

Type?

string

value?

Through scanf

value?

To be calculated

#include <stdio.h>

int main (void){

return (0);} // end of main

// declaration partint observed;char substance[20];

// input partprintf (“Enter the observed boiling point: \n”);scanf (“%d”, &observed);


2. EXAMPLE (3)


water_plus5 = (100 * 0.05) + 100;water_minus5 = (100 * 0.05) – 100;if (observed >= water_minus5) && (observed <= water_plus5) strcopy (substance, “water”);


2. EXAMPLE (3)


in the same way, calculate:mercury_plus5, mercury_minus5,copper_plus5, copper_minus5,silver_plus5, silver_minus5,gold_plus5, gold_minus5


2. EXAMPLE (3)


Don’t forget to declare your variables!!!


2. EXAMPLE (3)


Complete the if statement…and conclude your program

2. EXAMPLE (4)Write a program that calculates and prints the bill for Riyadh’s power consumption. The rates vary depending on whether the user is residential, commercial, or industrial. A code of R corresponds to a Residential, C corresponds to a Commercial, and I to Industrial. Any other code should be treated as an error.The program should read the power consumption rate in KWH (Kilowatt per Hour); then it calculates the due amount according to the following:The rate is SAR 5 per KWH for Residential, SAR 10 per KWH for Commercial and SAR 20 per KWH for Industrial.


2. EXAMPLE (4) – INPUT Write a program that calculates and prints the bill for Riyadh’s power consumption. The rates vary depending on whether the user is residential, commercial, or industrial. A code of R corresponds to a Residential, C corresponds to a Commercial, and I to Industrial. Any other code should be treated as an error.The program should read the power consumption rate in KWH (Kilowatt per Hour); then it calculates the due amount according to the following:The rate is SAR 5 per KWH for Residential, SAR 10 per KWH for Commercial and SAR 20 per KWH for Industrial.


2. EXAMPLE (4) – INPUT Write a program that calculates and prints the bill for Riyadh’s power consumption. The rates vary depending on whether the user is residential, commercial, or industrial. A code of R corresponds to a Residential, C corresponds to a Commercial, and I to Industrial. Any other code should be treated as an error.The program should read the power consumption rate in KWH (Kilowatt per Hour); then it calculates the due amount according to the following:The rate is SAR 5 per KWH for Residential, SAR 10 per KWH for Commercial and SAR 20 per KWH for Industrial.


2. EXAMPLE (4) – OUTPUT Write a program that calculates and prints the bill for Riyadh’s power consumption. The rates vary depending on whether the user is residential, commercial, or industrial. A code of R corresponds to a Residential, C corresponds to a Commercial, and I to Industrial. Any other code should be treated as an error.The program should read the power consumption rate in KWH (Kilowatt per Hour); then it calculates the due amount according to the following:The rate is SAR 5 per KWH for Residential, SAR 10 per KWH for Commercial and SAR 20 per KWH for Industrial.


2. EXAMPLE (4) – PROCESSINGWrite a program that calculates and prints the bill for Riyadh’s power consumption. The rates vary depending on whether the user is residential, commercial, or industrial. A code of R corresponds to a Residential, C corresponds to a Commercial, and I to Industrial. Any other code should be treated as an error.The program should read the power consumption rate in KWH (Kilowatt per Hour); then it calculates the due amount according to the following:The rate is SAR 5 per KWH for Residential, SAR 10 per KWH for Commercial and SAR 20 per KWH for Industrial.


Any C Program consists of the following parts: Preprocessor part Main function. This consists of the following: The declaration part The Initialization.

Documents