C programming examples with output

C programming examples with output

#-PREPROSESER

INCLUDE-ADD

STDIO.H-STANDERD INPUT OUTPUT///.H-HEADER FILE

CONIO.H-CONSOLE INPUT OUTPUT{ its means related to  output screen }

MATH.H-ALGORITHAM CALCULATION HEADER FILE

printf-to print on the display

scanf- to read the input

getch-hold the screen

void main()-preedefine function or main function

{-curly bresses start of programs body

}-curly bresses end of programs body

Example 1 - C hello world program
/** My first C program */

1. #include <stdio.h>
2.  
3. int main()
4. {
5.   printf("Hello World\n");
6.   return 0;
7. }

-------------------------------------------------------

Output of program:
"Hello World"

-------------------------------------------------------------------------------

Example 2 - C program to get input from a user using scanf

1. #include <stdio.h>
2.  
3. int main()
4. {
5.   int x;
6.  
7.   printf("Input an integer\n");
8.   scanf("%d", &x); // %d is used for an integer
9.  
10.   printf("The integer is: %d\n", x);
11.  
12.   return 0;
13. }

Output:
Input an integer
7897
The integer is: 7897

-----------------------------------------------------------------------------

Example 3 - using if else control instructions

1. #include <stdio.h>
2.  
3. int main()
4. {
5.    int x = 1;
6.  
7.    if (x == 1)
8.       printf("x is equal to one.\n");
9.    else
10.       printf("For comparison use '==' as '=' is the assignment operator.\n");
11.  
12.    return 0;
13. }

Output:
x is equal to one.

-------------------------------------------------------------------------------

Example 4 - while loop example

1. #include <stdio.h>
2.  
3. int main()
4. {
5.   int c = 1;  // Initializing variable
6.  
7.   while (c <= 10)  // While loop will execute till the condition is true
8.   {
9.     printf("%d ", c);  // Note the space after %d for gap in the numbers we want in output
10.     c++;
11.   }
12.  
13.   return 0;
14. }

Output:
1 2 3 4 5 6 7 8 9 10

------------------------------------------------------------------------------

Example 5 - C program check if an integer is prime or not

1. #include <stdio.h>
2.  
3. int main()
4. {
5.   int n, c;
6.  
7.   printf("Enter a number\n");
8.   scanf("%d", &n);
9.  
10.   if (n == 2)
11.     printf("Prime number.\n");
12.   else
13.   {
14.     for (c = 2; c <= n - 1; c++)
15.     {
16.       if (n % c == 0)
17.         break;
18.     }
19.     if (c != n)
20.       printf("Not prime.\n");
21.      else
22.        printf("Prime number.\n");
23.   }
24.   return 0;
25. }
26. ==============================================

Example 6 - command line arguments

1. #include <stdio.h>
2.  
3. int main(int argc, char *argv[])
4. {
5.   int c;
6.  
7.   printf("Number of command line arguments passed: %d\n", argc);
8.  
9.   for (c = 0; c < argc; c++)
10.     printf("%d argument is %s\n", c + 1, argv[c]);
11.  
12.   return 0;
13. }
14. ==================================================

This program prints the number of arguments passed, and the arguments which are passed to it.

Example 7 - Array program

1. #include <stdio.h>
2.  
3. int main()
4. {
5.     int array[100], n, c;
6.    
7.     printf("Enter number of elements in array\n");
8.     scanf("%d", &n);
9.    
10.     printf("Enter %d elements\n", n);
11.    
12.     for (c = 0; c < n; c++)
13.         scanf("%d", &array[c]);
14.    
15.     printf("The array elements are:\n");
16.    
17.     for (c = 0; c < n; c++)
18.         printf("%d\n", array[c]);
19.    
20.     return 0;
21. }
22. =========================================

Example 8 - function program

1. #include <stdio.h>
2.  
3. void my_function();  // Declaring a function
4.  
5. int main()
6. {
7.   printf("Main function.\n");
8.  
9.   my_function();  // Calling the function
10.  
11.   printf("Back in function main.\n");
12.  
13.   return 0;
14. }
15.  
16. // Defining the function
17. void my_function()
18. {
19.   printf("Welcome to my function. Feel at home.\n");
20. }
21. =========================================================

Example 9 - Using comments in a program

1. #include <stdio.h>
2.  
3. int main()
4. {
5.    // Single line comment in a C program
6.  
7.    printf("Writing comments is very useful.\n");
8.  
9.    /*
10.     * Multi-line comment syntax
11.     * Comments help us to understand program later easily.
12.     * Will you write comments while writing programs?
13.     */
14.  
15.    printf("Good luck C programmer.\n");
16.  
17.    return 0;
18. }
19. ======================================================

Example 10 - using structures in C programming

1. #include <stdio.h>
2. #include <string.h>
3.  
4. struct game
5. {
6.   char game_name[50];
7.   int number_of_players;
8. };  // Note the semicolon
9.  
10. int main()
11. {
12.   struct game g;
13.  
14.   strcpy(g.game_name, "Cricket");
15.   g.number_of_players = 11;
16.  
17.   printf("Name of game: %s\n", g.game_name);
18.   printf("Number of players: %d\n", g.number_of_players);
19.  
20.   return 0;
21. }
22. ==============================================

Example 11 - C program for Fibonacci series

1. #include <stdio.h>
2.  
3. int main()
4. {
5.   int n, first = 0, second = 1, next, c;
6.  
7.   printf("Enter the number of terms\n");
8.   scanf("%d", &n);
9.  
10.   printf("First %d terms of Fibonacci series are:\n", n);
11.  
12.   for (c = 0; c < n; c++)
13.   {
14.     if (c <= 1)
15.       next = c;
16.     else
17.     {
18.       next = first + second;
19.       first = second;
20.       second = next;
21.     }
22.     printf("%d\n", next);
23.   }
24.  
25.   return 0;
26. }
27. ==============================================

Example 12 - C graphics programming

1. #include <graphics.h>
2. #include <conio.h>
3.  
4. int main()
5. {
6.     int gd = DETECT, gm;
7.    
8.     initgraph(&gd, &gm,"C:\\TC\\BGI");
9.    
10.     outtextxy(10, 20, "Graphics programming is fun!");
11.    
12.     circle(200, 200, 50);
13.    
14.     setcolor(BLUE);
15.    
16.     line(350, 250, 450, 50);
17.    
18.     getch();
19.     closegraph( );
20.     return 0;
21. }
22. 
    
23. --------------------------------------------------------------

    How to compile C programs with GCC compiler?

    If you are using GCC on Linux operating system, then you may need to modify the programs. For example, consider the following program which prints first ten natural numbers
    1. #include <stdio.h>
    2. #include <conio.h>
    3.  
    4. int main()
    5. {
    6.     int c;
    7.  
    8.     for (c = 1; c <= 10; c++)
    9.         printf("%d\n", c);
    10.    
    11.     getch();
    12.     return 0;
    13. }
    Above program includes a header file <conio.h> and uses function getch, but this file is Borland specific, so it works in Turbo C compiler but not in GCC. The program for GCC should be like:
    1. #include <stdio.h>
    2.  
    3. int main()
    4. {
    5.     int c;
    6.  
    7.     /* for loop */
    8.  
    9.     for (c = 1; c <= 10; c++)
    10.         printf("%d\n", c);
    11.    
    12.     return 0;
    13. }
    If using GCC then save the program in a file say “numbers.c” to compile the program open the terminal and enter the command “gcc numbers.c” this will compile the program and to execute the program enter the command “./a.out” do not use quotes while executing commands. You can specify the output file name as: gcc numbers.c -o numbers.out, to run execute ./numbers.out in the terminal.
24. =========================================================
25. PROGRAMER BABU

PROGRAMER BABU