编辑代码

#include <stdio.h>
void swap (int *a,int *b)
{
    int tmp;
    tmp = *a; *a=*b; *b=tmp;
}
int main () {
    int n1,n2;
    n1=1,n2=2;
    swap(&n1,&n2);
    printf("%d %d",n1,n2);
}