BZOJ2301: [HAOI2011]Problem b 莫比乌斯反演

#include<cstdio>
#include<cstring>
#include<queue>
#include<cstdlib>
#include<algorithm>
#include<vector>
#include<cmath>
using namespace std;
typedef long long LL;
const int N=5e4+5;
const int INF=0x3f3f3f3f;
bool vis[N];
int prime[N],mu[N],cnt;
void getmu()
{
    mu[1] = 1;
    for(int i=2; i<=N-5; i++)
    {
        if(!vis[i])
        {
            prime[++cnt] = i;
            mu[i] = -1;
        }
        for(int j=1; j<=cnt&&i*prime[j]<=N-5; j++)
        {
            vis[i*prime[j]] = 1;
            if(i%prime[j]) mu[i*prime[j]] = -mu[i];
            else
            {
                mu[i*prime[j]] = 0;
                break;
            }
        }
    }
}
LL solve(int n,int m,int k){
   n/=k,m/=k;
   int l=min(n,m);
   LL ans=0;
   for(int i=1,j;i<=l;i=j+1){
     j=min(n/(n/i),m/(m/i));
     ans+=1ll*(mu[j]-mu[i-1])*(n/i)*(m/i);
   }
   return ans;
}
int main(){
    getmu();
    for(int i=1;i<=N-5;++i)mu[i]+=mu[i-1];
    int T;
    scanf("%d",&T);
    while(T--){
       int a,b,c,d,k;
       scanf("%d%d%d%d%d",&a,&b,&c,&d,&k);
       printf("%lld\n",solve(b,d,k)-solve(b,c-1,k)-solve(a-1,d,k)+solve(a-1,c-1,k));
    }   
    return 0;
}