#include<bits/stdc++.h>
using namespace std;
int a[] = {2,1,3,4,5,9,10,11,4,19};
int tmp[20];
void m_sort(int a[], int L, int R)
{
    if(L>=R){
        return ;
    }

    int mid = (L+R)/2;

    cout <<"左侧： ";
    for(int i=L; i<=mid; i++){
        cout << a[i] << " ";
    }
    cout <<"右侧： ";
    for(int i=mid+1; i<=R; i++){
        cout << a[i] << " ";
    }
    cout << endl;

    m_sort(a, L , mid);
    m_sort(a, mid+1, R);

    int i = L , j = mid+1, k = L;

    while(i <= mid && j <= R){
        if(a[i] < a[j]){
            tmp[k++] = a[i++] ;
        }else{
            tmp[k++] = a[j++];
        }
    }

    while(i<=L){
        tmp[k++] = a[i++];
    }

    while(j<=R){
        tmp[k++] = a[j++];
    }


    for(int i=L; i<=R;i++){
        a[i]= tmp[i];
    }





    return ;


}
int main(){
    for(int i=0; i<10; i++){
        cout <<a[i] << " ";
    }
    cout << endl; 
    m_sort(a, 0, 9);

    for(int i=0; i<10; i++){
        cout <<a[i] << " ";
    }

    return 0;
}

—— 本文来自火龙信奥（义乌睿码科技）：义乌青少年信息学奥赛与编程教育平台，专注 CSP-J/S、NOIP、GESP 竞赛培训，线上线下融合教学，助力编程升学。网址：hlcoding.com