#include <iostream>
#include <vector>
using namespace std;

void merge(vector<int>& A, vector<int> L, vector<int> R) {
    int l = L.size();
    int r = R.size();
    int i = 0;
    int j = 0;
    int k = 0;
    while(i < l && j < r) {
        if(L[i] < R[j]) {
            A[k++] = L[i++];
        } else {
            A[k++] = R[j++];
        }
    }
    while(i < l) A[k++] = L[i++];
    while(j < r) A[k++] = R[j++];
}

void mergesort(vector<int>& arr) {
    int n = arr.size();
    if(n < 2) return;
    int mid = n/2;
    int i;
    vector<int> L(mid);
    vector<int> R(n - mid);
    for(i = 0; i < mid; ++i) {
        L[i] = arr[i];
    }
    for(;i < n; ++i) {
        R[i-mid] = arr[i];
    }
    mergesort(L);
    mergesort(R);
    merge(arr, L, R);
}

int main() {
    int arr[10] = {2, 5, 4, 3, 1, 6, 8, 9, 7, 0};
    vector<int> Arr(arr, arr + 10);
    for(int i = 0; i < 10; ++i)
        cout << Arr[i] << " ";
    cout << endl;
    mergesort(Arr);
    for(int i = 0; i < 10; ++i)
        cout << Arr[i] << " ";
    return 0;
}