Working process of printf()

   1)      In printf() a format specifier associate with outside value left to left.

Example:- int a =10, b=5;

                printf(“a=%d,b=%d",a,b);

Output----- a=10,b=5

   2)      In printf(), a work will be perform right to left.

Example:- int a;

                        printf(“a=%d”,a,++a,a=20);

Output----- a=21

   3)      When outside value received into first double quotes of printf() then printf() display it on monitor.

example:- int a=20;

                        printf(“a=10”,a,++a,a=20);

Output----- a=21

   4)      Lastly printf() returns total number of character enclosed within it’s first double quotes.

Example:- int r;

                r=printf(“Wel %s”,”come”);

                    printf(“\n r= %d”,r);

Output------ Welcome

                                r= 7

Working process of scanf()

An inbuit function scanf() perform a work as a following way:-

(i)                  In scanf() a format specifier associate with variable left to left.

Example:- scanf(“%d %d”,&a,&b);

(ii)                Lastly scanf() returns total number of value accepted from keyboard.

Exampl\e:- printf(“enter two number”);

                        r=scanf(“%d %d”,&a,&b);

                        printf(“r=%d”,r);

Output------à enter two number 5

10

r=2

Explanation:-

    1)      write a program in C to accept one integer and one fractional number from keyboard  and display its product.

void main()

{

                                int a;

                                float b;

                                clrscr();

                                printf(“Enter two number:”);

                                scanf(“%d @ %f”,&a,&b);

                                printf(“a*b = %f”,a*b);

                                getch();

                }

Output-----à Enter two number:5 @ 2.5

                                a*b=12.5

    2)      void main()

{

int a,b,r;

clrscr();

r=printf(“\n%d,%d”,scanf(“%d%d”,&a,7b),printf(“enter two number:”));

printf(“\n r=%d”,r);

getch();

}

Output----à enter two number: 5

                                10

                                2,13

                                r=5