2_4.cpp

#include <iostream>
#include <pcg_random.hpp>
#include <random>
#include <unordered_map>
#include <vector>
using namespace std;

int main() {
    cout.precision(4);
    int N = 0;
    vector<int> arr;

    // cin >> N;
    // for (int i = 0; i < N; i++) {
    //     double tmp;
    //     cin >> tmp;
    //     arr.push_back(tmp);
    // }

    // generate test data
    pcg_extras::seed_seq_from<std::random_device> seed_source;
    pcg32 rng(seed_source);
    std::uniform_int_distribution dist(1, 10);
    N = 10;
    for (int i = 0; i < N; i++)
        arr.push_back(dist(rng));

    cout << "arr size:" << arr.size() << endl;
    for (const auto &i: arr)
        cout << i << ", ";
    cout << endl;

    unordered_map<int, int> map;
    for (const int &i: arr) {
        if (!map.contains(i)) {
            map[i] = 1;
        } else {
            map[i] = map[i] + 1;
        }
    }
    int modeValue = 0, modeCount = 0;
    for (const auto &[fst, snd]: map) {
        if (snd > modeCount) {
            modeCount = snd;
            modeValue = fst;
        }
    }

    // ranges::sort (arr);
    // for (auto &i : arr)
    //   cout << i << ", ";
    // cout << endl;
    // cout << "modeValue:" << modeValue << ", modeCount:" << modeCount << endl;
    cout << endl << "answer:" << endl;
    cout << modeValue << endl;
    return 0;
}