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#ifndef LIGHTNING_COMMON_RANDOM_SELECT_H
#define LIGHTNING_COMMON_RANDOM_SELECT_H
#include "config.h"
#include <stdbool.h>
/* Use weighted reservoir sampling, see:
* https://en.wikipedia.org/wiki/Reservoir_sampling#Algorithm_A-Chao
* But (currently) the result will consist of only one sample (k=1)
*/
/**
* random_select: return true if we should select this one.
* @weight: weight for this option (use 1.0 if all the same)
* @tot_weight: returns with sum of weights (must be initialized to zero)
*
* This always returns true on the first non-zero weight, and weighted
* randomly from then on.
*/
bool random_select(double weight, double *tot_weight);
#endif /* LIGHTNING_COMMON_RANDOM_SELECT_H */