12 // random number should be in [0, arr[len - 1])
13 // If by chance arr[len - 1] == 0.0, one possibility is to sample uniformly from 0 ... len - 1
14 int sample(double* arr, int len) {
16 double prb = random() * arr[len - 1];
22 if (arr[mid] <= prb) l = mid + 1;
26 if (l >= len) { printf("%d %lf %lf\n", len, arr[len - 1], prb); }
32 virtual double random() { return 0.0; };