#include<stdio.h> // function prototype, also called function declaration float square ( float x ); // main function, program starts from here int main( ) { float m, n ; printf ( "\nEnter some number for finding square \n"); scanf ( "%f", &m ) ; // function call n = square ( m ) ; printf ( "\nSquare of the given number %f is %f",m,n ); } float square ( float x ) // function definition { float p ; p = x * x ; return ( p ) ; }