printf( ) & scanf( ):
printf() and scanf() functions are library functions in C programming language defined in “stdio.h”.
printf() function is used to print the character, string, float, integer, octal and hexadecimal values onto the output screen.
scanf() function is used to read character, string, numeric data from keyboard.
%d format specifier is used in printf() and scanf() to specify the value of an integer variable.
%c is used to specify character,
%f for float variable, %s for string variable, and %x for hexadecimal variable.
Example:
#include<stdio.h>
#include<conio.h>
void main() {
int i;
clrscr();
printf("Enter a number");
scanf("%d",&i);
printf("Entered number is: %d",i);
getch();
}