#include<iostream>
#include<random>
#include<fstream>
#include<map>
using namespace std;
 
int main(){
 
    mt19937 mt; //The Mersenne Twister is a pseudorandom number generator (PRNG), default_seed is a member constant, defined as 5489u;
    exponential_distribution<double> exponential_intervals(20.0);
    double interval;
    double timestamp = 0;
    size_t count = 10000;
    for(int j = 0; j < count; j ++){
        interval = exponential_intervals(mt);
        //cout<<interval<<endl;
        timestamp += interval;  //generate exponentional distribution randoms, in micro seconds
    }
 
    cout << count/timestamp << endl;
}

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