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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// REQUIRES: long_tests
// <random>
// template<class IntType = int>
// class discrete_distribution
// template<class _URNG> result_type operator()(_URNG& g, const param_type& parm);
#include <cassert>
#include <cstdlib>
#include <random>
#include <vector>
int main(int, char**)
{
{
typedef std::discrete_distribution<> D;
typedef D::param_type P;
typedef std::minstd_rand G;
G g;
D d;
double p0[] = {.3, .1, .6};
P p(p0, p0+3);
const int N = 10000000;
std::vector<D::result_type> u(3);
for (int i = 0; i < N; ++i)
{
D::result_type v = d(g, p);
assert(0 <= v && v <= 2);
u[v]++;
}
std::vector<double> prob = p.probabilities();
for (int i = 0; i <= 2; ++i)
assert(std::abs((double)u[i]/N - prob[i]) / prob[i] < 0.001);
}
return 0;
}
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