2017 Multi-University Training Contest - Team 2 &&hdu 6053 TrickGCD

TrickGCD

Time Limit: 5000/2500 MS (Java/Others)    Memory Limit: 262144/262144 K (Java/Others)
Total Submission(s): 2097    Accepted Submission(s): 816

Sample Input

1

4

4 4 4 4

Sample Output

Case #1: 17

 

Source

2017 Multi-University Training Contest - Team 2

最近不舒服 病了 找个时间来解释

 #include<iostream>
 #include<cstdio>
 #include<algorithm>
 #include<cstring>
 #include<cstdlib>
 #include<string.h>
 #include<set>
 #include<vector>
 #include<queue>
 #include<stack>
 #include<map>
 #include<cmath>
 typedef long long ll;
 typedef unsigned long long LL;
 using namespace std;
 const double PI=acos(-1.0);
 const double eps=0.0000000001;
 const int N=+;
 const int mod=1e9+;
 const int INF=0x3f3f3f3f;
 int num[N],mo[N];
 void mobius(){
     mo[]=;
     for(int i=;i<=N;i++)
     for(int j=i+i;j<=N;j+=i)
     mo[j]-=mo[i];
 }
 int pow_mod(int a,int b){
     ll ans=;
     while(b)
     {
         if(b&)ans=(ans*a)%mod;
         a=(1ll*a*a)%mod;
         b>>=;
     }
     return ans;
 }
 int main(){
     int t,n,x,minn,kase=;
     mobius();
     scanf("%d",&t);
     while(t--)
     {
         memset(num,,sizeof(num));
         for(int i=;i<=N;i++){
             num[i]=num[i-]+num[i];
         }
         minn=INF;
         scanf("%d",&n);
         for(int i=;i<=n;i++){
             scanf("%d",&x);
             minn=min(minn,x);
             num[x]++;
         }
         ll ans=;
         for(int i=;i<=minn;i++)
         {
             int cnt=;
             for(int j=;j*i<=;j++)
             {
                 cnt=((ll)*cnt*pow_mod(j,num[i*(j+)-]-num[i*j-]))%mod;
             }
             ans=(ans-(ll)*mo[i]*cnt+mod)%mod;
         }
         printf("Case #%d: %lld\n",++kase,ans);
     }
     return ;
 }