A simple function to generate random integers in a specified range using modern C++ random functions. Inspired by Stephan T. Lavavej's 2013 talk: https://channel9.msdn.com/Events/GoingNative/2013/rand-Considered-Harmful

easy_rand.h

/**
 * @file easy_rand.h
 * 
 * Makes it easy to generate good pseudo-random values in a
 * given numerical range using the new C++11 <random> features,
 * without the setup overhead.
 */
#ifndef EASY_RAND_H
#define EASY_RAND_H

#include <random>

/**
 * @brief   returns a pseudo-random integer in the interval [low, high]
 * @details Sets up an mt19937 Mersenne Twister random number generator
 *          using a random seed obtained from the best entropy source
 *          available to the <random> library.
 *          Note: Setup time on the first call to this function will cause 
 *          the first call to be slightly slower than subsequent 
 *          calls.
 * 
 * @param low  lower-bound of interval for random value (included in interval)
 * @param high upper-bound of interval for random value (included in interval)  
 * 
 * @return pseudo-random integer in the range [low, high]
 */
int rand_between(int low, int high){
    static std::random_device            seeder;                    // used to seed with system entropy
    static std::mt19937                  generator{seeder()};       // set up (and seed) the PRNG
    std::uniform_int_distribution<int>   distribution{low, high};   // set up distribution for requested range
    return distribution(generator);                                 // generate and return result
}

#endif