康拓展开

 1 #include <iostream>
 2 #include <cstdlib>
 3 #include <cstring>
 4 #include <queue>
 5 #include <cstdio>
 6 #include <algorithm>
 7 #include <map>
 8 #define LL long long
 9
10 using namespace std;
11
12 //X = a[1]*(n-1)!+a[2]*(n-2)!+...+a[i]*(n-i)!+...+a[n-1]*1!+a[n]*0!
13 //其中a[i]表示在num[i+1..n]中比num[i]小的数的数量
14
15 void Cantor(int nums[],int n)
16 {
17     int fact[15];
18     fact[0] = 1;
19     fact[1] = 1;
20     for(int i = 2; i <= 13; i++)
21         fact[i] = fact[i-1]*i;
22
23     int cnt = 0;
24     for(int i = 1; i <= n; i++)
25     {
26         int tmp = 0;
27         for(int j = i+1; j <= n; j++)
28             if(nums[j] < nums[i])
29             tmp++;
30         cnt +=  tmp * fact[n-i];
31     }
32     printf("%d\n",cnt+1);
33 }
34
35
36 void solve()
37 {
38     int nums[1000];
39     int n;
40     scanf("%d",&n);
41     for(int i = 1; i <= n; i++)
42         scanf("%d",&nums[i]);
43     Cantor(nums,n);
44 }
45
46 int main(void)
47 {
48     int t;
49     scanf("%d",&t);
50     while(t--)
51     {
52         solve();
53     }
54     return 0;
55 }