|
//http://acm.hdu.edu.cn/showproblem.php?pid=2001
|
|
#include <cstdio>
|
|
#include <cmath>
|
|
|
|
int main(int argc,char ** argv){
|
|
double x1,y1,x2,y2;
|
|
while(scanf("%lf%lf%lf%lf",&x1,&y1,&x2,&y2)!=EOF){
|
|
printf("%.2f\n",sqrt(pow(x1-x2,2)+pow(y1-y2,2)));
|
|
}
|
|
return 0;
|
|
} |