#include <bits/stdc++.h>   using namespace std;   int main() {     int nCase;     scanf( %d , &nCase);     while (nCase--) {       int a, b;       scanf( %d%d , &a, &b);       if (a == 0) {         if (b == 0)           printf( 1 n );         else           printf( 0.5 n );         continue;       }       if (b == 0) {         printf( 1 n );         continue;       }       b *= 4;       if (a >= b)         printf( %.6f n , (0.5 * (a - b + a) * b + 1.0 * a * b) / (2.0 * b * a));       else         printf( %.6f n , (1.0 * a * b + 0.5 * a * a) / (2.0 * b * a));     }     return 0;   }   