自定义函数

#pragma warning(disable:4996)
#include<stdio.h>
int z(int x,int y)
{
  if (x > y)
    return x;
  else
    return y;
}
int main()
{
  int m = 0;
  int n = 0;
  printf("请输入想比较的两个数：");
  scanf("%d%d", &m, &n);
  int max = z(m, n);
  printf("max=%d\n", max);
  return 0;
}

加减乘除自定义函数和比大小的自定义函数都大同小异，但是下面的交换数值，就有点不一样了

#pragma warning(disable:4996)
#include<stdio.h>
jiaohuan(int* pm, int* pn)
{
  int z = *pm;
  *pm = *pn;
  *pn = z;
}
int main()
{
  int m = 0;
  int n = 0;
  printf("请输入你想交换的两个数字：");
  scanf("%d%d", &m, &n);
  printf("m=%d n=%d—（初始）\n", m, n);
  jiaohuan(&m, &n);
  printf("m=%d n=%d—（交换后）", m, n);
  return 0;
}