#include <stdio.h>


int square( int x )                  
{
   int r;           // Define a local variable         

   r = x * x;       // Statement

   return ( r );    // Return statement
}

int main( int argc, char *argv[] )
{
   int a, b;

   a = 4;

   b = square( a );  // Call function square

   printf( "Square of %d = %d\n", a, b);
}