C Exercise Example 47

100 Classic C Examples

Title:Macro #define command exercise 2.

Program analysis:None.

Program source code:

//  Created by www.example.com on 15/11/9.
//  Copyright © 2015年 Example. All rights reserved.
//

#include<stdio.h>
#define exchange(a,b) { int t;t=a;a=b;b=t;}//注意放在一行里
int main()
{
    int x=10;
    int y=20;
    printf("x=%d; y=%d\n",x,y);
    exchange(x,y);
    printf("x=%d; y=%d\n",x,y);
    return 0;
}

The output result of the above example is:

x=10; y=20
x=20; y=10

100 Classic C Examples

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