#include <stdio.h>

int x = 1;		// Global variable

void f( )
{
   int y = 4;		// Local variable

   printf("x = %d, y = %d\n", x, y ); // global x, local y
}


int main(int argc, char *argv[] )
{
   int z = 2;		// Local variable

   printf("x = %d, z = %d\n", x, z );  // global x, local z

   x = 777;             // Update the global variable
   f( );
}