C语言调用函数

#include <stdio.h>

/* function declaration */
int max(int num1, int num2);

int main () {

   /* local variable deFinition */
   int a = 100;
   int b = 200;
   int ret;

   /* 调用函数 */
   ret = max(a, b);

   printf( "Max value is : %d\n", ret );

   return 0;
}

/* function returning the max between two numbers */
int max(int num1, int num2) {

   /* local variable declaration */
   int result;

   if (num1 > num2)
      result = num1;
   else
      result = num2;

   return result; 
}