HDU 计算两点间的距离

粗心 输入顺序错了 引以为戒

#include<stdio.h>
#include<math.h>
int main(){
double x1,x2,y1,y2;
double i;
    while(scanf("%lf %lf %lf %lf",&x1,&y1,&x2,&y2) != EOF )
    {
    i=sqrt ( (x1-x2)*(x1-x2)+(y1-y2)*(y1-y2) );
    printf("%.2f\n",i);
    }

return 0;
}