題解：
1 #pragma comment(linker, "/STACK:1024000000,1024000000")
2 #include<iostream>
3 #include<cstdio>
4 #include<cstring>
5 #include<cmath>
6 #include<math.h>
7 #include<algorithm>
8 #include<queue>
9 #include<set>
10 #include<bitset>
11 #include<map>
12 #include<vector>
13 #include<stdlib.h>
14 using namespace std;
15 #define ull unsigned long long int
16 #define eps 1e-10
17 #define MOD 1000000007
18 #define N 1000000
19 #define inf 1e12
20 ull n;
21 int main()
22 {
23 int t;
24 scanf("%d",&t);
25 while(t--){
26 scanf("%I64u",&n);
27 ull ans=0;
28 if(n>=4)
29 ans=ans+n*(n-1)/2*(n-2)/3*(n-3)/4;
30 ans+=n;
31 printf("%I64u\n",ans);
32 }
33 return 0;
34 } View Code