题解 100% AC

#include<bits/stdc++.h>
using namespace std;
int n,a[1010],temp[1010];
void MergeSort(int l,int r){
	if(l==r)return;
	int mid =(l+r)>>1;
	MergeSort(l,mid);
	MergeSort(mid+1,r);
    int i=l,j=mid+1,k=l;
	while(i<=mid&&j<=r){
		if(a[i]<=a[j])temp[k++]=a[i++];
		else temp[k++]=a[j++];
	}
	while(i<=mid)temp[k++]=a[i++];
	while(j<=r)temp[k++]=a[j++];
	for(int i=l;i<=r;i++)a[i]=temp[i];
	for(int i=1;i<=n;i++)cout<<a[i]<<" ";
	cout<<endl;
}
int main(){
	cin>>n;
	for(int i=1;i<=n;i++)cin>>a[i];
	MergeSort(1,n);
	return 0;
}