HDU 1040 As Easy As A+B 快排

 1 #include<cstdio>
 2 #include<cmath>
 3 #include<cstring>
 4 #include<iostream>
 5 using namespace std;
 6 int n,a[100000];
 7 void qsort(int l,int r)
 8 {
 9     int i=l;
10     int j=r;
11     int x=a[(l+r)/2];
12     do{
13     while (a[i]<x)
14     i++;
15     while (a[j]>x)
16     j--;
17     if(j>=i)
18     {
19         int y=a[i];
20         a[i]=a[j];
21         a[j]=y;
22         i++;
23         j--;
24     }    }
25     while (i<j);
26     if( l<j)
27     qsort(l,j);
28     if(i<r)
29     qsort(i,r);
30     
31     
32 }
33 int main(){
34     int t;
35     scanf("%d",&t);
36     while(t--)
37     {
38       scanf("%d",&n);
39       for (int i=1;i<=n;++i)
40       {
41           scanf("%d",&a[i]);
42       }    
43       qsort(1,n);
44       for (int i=1;i<=n-1;++i)
45       {
46           printf("%d ",a[i]);
47       }
48       printf("%d\n",a[n]);
49     }
50     return 0;
51 }