题解 | #排序#

快速排序
#include<iostream>
#include<algorithm>
using namespace std;

int partition(int arr[],int l,int r) 
{
	int m = arr[l];
	while (l < r) {
		while (l < r && m <= arr[r]) r--;
		arr[l] = arr[r];
		while (l < r && arr[l] <= m) l++;
		arr[r] = arr[l];

	}
	arr[l] = m;
	return l;
}


void quicksort(int arr[],int l, int r) 
{
	if (l >= r) return ;
	int m = partition(arr,l, r);
	quicksort(arr, l, m - 1);
	quicksort(arr,m + 1,r);
	

}

int main() {
	int n;
	int arr[101];
	scanf("%d", &n);
	for (int i = 0; i < n; i++) {
		cin >> arr[i];

	}
	quicksort(arr, 0, n-1);
	for (int i = 0; i < n; i++) {
		cout << arr[i] << ' ';

	}

}