1306.Sequence Median（堆排序）

URAL真是没水题以为简单的排序就好了 ME 内存限制很紧堆排序或者 STL

用堆排序做的正好复习一下都忘了

 1 #include <iostream>
 2 #include<cstdio>
 3 #include<cstring>
 4 #include<algorithm>
 5 #include<stdlib.h>
 6 using namespace std;
 7 #define N 1250010
 8 int a[N];
 9 void adjust(int i,int n)
10 {
11     int j;
12     a[0] = a[i];
13     j = 2*i;
14     while(j<=n)
15     {
16         if(j<n&&a[j+1]>a[j])
17         j++;
18         if(a[0]<a[j])
19         {
20             a[i] = a[j];
21             i = j;
22             j = 2*i;
23         }
24         else
25         break;
26     }
27     a[i] = a[0];
28 }
29 int main()
30 {
31     int i,j,n,t,x;
32     scanf("%d",&n);
33     int k = n/2+1;
34     for(i = 1; i <= k ; i++)
35     scanf("%d",&a[i]);
36     if(n==2)
37     {
38         printf("%.1lf
",(a[2]/2.0+a[1]/2.0));
39         return 0;
40     }
41     for(i = k/2 ; i>= 1 ; i--)
42     adjust(i,k);
43     for(i = k+1 ; i <= n ; i++)
44     {
45         scanf("%d",&x);
46         if(x<a[1])
47         {
48             a[1] = x;
49             adjust(1,k);
50         }
51     }
52     for(i = k ; i >1 ; i--)
53     {
54         t = a[1];
55         a[1] = a[i];
56         a[i] = t;
57         adjust(1,i-1);
58     }
59     if(n%2!=0)
60     printf("%.1lf
",1.0*a[k]);
61     else
62     printf("%.1lf
",a[k-1]/2.0+a[k]/2.0);
63     return 0;
64 }

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