【bzoj 2301】Problem b（莫比乌斯反演）

传送门biu~

#include<bits/stdc++.h>using namespace std;int u[100005],prime[100005],tp;bool b[100005];void get_u(){    u[1]=1;    for(int i=2;i<=100000;++i){        if(!b[i])   prime[++tp]=i,u[i]=-1;        for(int j=1;j<=tp && i*prime[j]<=100000;++j){            b[i*prime[j]]=true;            if(i%prime[j]==0)   break;            u[i*prime[j]]=-u[i];        }    }    for(int i=1;i<=100000;++i)  u[i]+=u[i-1];}long long calc(int n,int m,int k){    n/=k;   m/=k;    int pre;    long long re=0;    for(int i=1;i<=n && i<=m;i=pre+1){        pre=min(n/(n/i),m/(m/i));        re+=1ll*(n/i)*(m/i)*(u[pre]-u[i-1]);    }    return re;}int main(){    int n;    scanf("%d",&n);    get_u();    while(n--){        int a,b,c,d,k;        scanf("%d%d%d%d%d",&a,&b,&c,&d,&k);        printf("%lld\n",calc(b,d,k)+calc(a-1,c-1,k)-calc(a-1,d,k)-calc(b,c-1,k));    }    return 0;}