#include <stdio.h>

// global variable
int max;

void findMax(int a, int b, int c) {
  int tmpmax = a;  // local variable holding the temp max value 
  if (b > tmpmax) {
    if (c > b) tmpmax = c;
    else       tmpmax = b;
  } else if (c > tmpmax) tmpmax = c;
  max = tmpmax;
}

int main(void) {
  findMax(4, 3, 7);
  printf("The maximum number is: %d\n", max);

  return 0;
}