宏定义和带参数的宏

#include<iostream>
using namespace std;
//不带参数的宏
#define PI 3.1415926
//带参数的宏
#define FUN(x) x*x
#define FUN2(x) (x)*(x)
#define MAX(x,y) x>y?x:y
int main(void){
    int i = 10;
  int j = FUN(i);//j = i*i   10*10
  cout << j << endl;//100
  int x = 10;
  int y = 20;
  int z = MAX(x, y);//x>y?x:y
  cout << z << endl;//20
  //特别注意:
  int m = FUN(2 + 3);//正确结果:2+3*2+3  错误结果:5*5
  cout << m << endl;//11
  //区别:
  int m2 = FUN2(2 + 3);//正确结果:(2+3)*(2+3)  
  cout << m << endl;//25
  system("pause");
  return 0;
}