codechef CIELDIST - "Minimum Distance" solution

codechef CIELDIST - "Minimum Distance" : http://www.codechef.com/problems/CIELDIST

codechef CIELDIST - "Minimum Distance" editorial : http://discuss.codechef.com/questions/5605/cieldist-editorial

codechef CIELDIST - "Minimum Distance" solution :  http://ideone.com/lXMqNi

#include <iostream>
#include <cstdio>
using namespace std;

int main() {
int t, ds, dt, d;
scanf("%d", &t);
while(t--) {
scanf("%d%d%d", &ds, &dt, &d);
double r;
if(d>=ds+dt) r=d-ds-dt;
else if(ds>=d+dt) r=ds-d-dt;
else r=dt-d-ds;
if(r<0) r=0;
printf("%.8lf\n", r);
}
return 0;
}

note: