将a和b交换的3种方法

方法1

#include <stdio.h>int main(){int a,b;int c;scanf("%d%d",&a,&b);c=a;a=b;b=c;printf("%d%d",a,b);return 0;} 

方法2

#include <stdio.h>int main(){int a,b;scanf("%d%d",&a,&b);a=a+b;b=a-b;a=a-b;printf("%d%d\n",a,b);} 

方法3

#include <stdio.h>int main(){int a,b;scanf("%d%d",&a,&b);printf("%d%d",b,a);return 0;}