Acwing785. Quick sort

Give you a length of  n  The whole number sequence of .

Please use quick sort to sort this sequence from small to large .

And output the ordered sequence in order .

Input format

There are two lines of input , The first line contains integers  n.

The second line contains  n It's an integer （ All integers are in  1∼10^9 Within the scope of ）, Represents the whole sequence of numbers .

Output format

The output is one line , contain  n  It's an integer , It's an ordered sequence .

Data range

1≤n≤100000

sample input ：

5
3 1 2 4 5

sample output ：

1 2 3 4 5

#include <iostream>
#include <cstring>
#include <algorithm>

using namespace std;

const int N = 100010;

int q[N];

void quick_sort(int q[], int l, int r)
{
    if (l >= r) return; 

    int i = l - 1, j = r + 1, x = q[l + r >> 1];
    while (i < j)
    {
        do {
            i ++;
        }while (q[i] < x);
        do{
            j -- ;
            
        }while (q[j] > x);
        if (i < j) swap(q[i], q[j]);
    }

    quick_sort(q, l, j);
    quick_sort(q, j + 1, r);
}

int main()
{
    int n;
    scanf("%d", &n);

    for (int i = 0; i < n; i ++ ) scanf("%d", &q[i]);

    quick_sort(q, 0, n - 1);

    for (int i = 0; i < n; i ++ ) printf("%d ", q[i]);

    return 0;
}