【BZOJ】【P2301】【HAOI2011】【Problem b】【题解】【莫比乌斯反演】

来源：互联网发布：数字病理人工智能编辑：程序博客网时间：2024/06/05 21:09

传送门:http://www.lydsy.com/JudgeOnline/problem.php?id=2301

事实证明刷完一个zap就可以水很多题了……

Code:

#include<cstdio>#include<iostream>#include<algorithm>#include<cctype>using namespace std;typedef long long LL;const int maxn=50005;int T,n,m;bool p[maxn];int u[maxn],prime[maxn];int getint(){int res=0;char c=getchar();while(!isdigit(c))c=getchar();while(isdigit(c))res=res*10+c-'0',c=getchar();return res;}void init(){u[1]=1;for(int i=2;i<maxn;i++){if(!p[i]){prime[++prime[0]]=i;u[i]=-1;}for(int j=1;i*prime[j]<maxn&&j<=prime[0];j++){int K=i*prime[j];p[K]=1;if(i%prime[j]==0){u[K]=0;break;}else u[K]=-u[i];}}for(int i=2;i<maxn;i++)u[i]+=u[i-1];}LL calc(int n,int m,int k){n/=k;m/=k;if(n>m)swap(n,m);LL ans=0;for(int i=1,last;i<=n;i=last+1){last=min(n/(n/i),m/(m/i));ans+=(LL)(u[last]-u[i-1])*(n/i)*(m/i);}return ans;}int main(){T=getint();init();while(T--){int a=getint(),b=getint(),c=getint(),d=getint(),k=getint();LL ans=calc(b,d,k)-calc(a-1,d,k)-calc(b,c-1,k)+calc(a-1,c-1,k);printf("%lld\n",ans);}return 0;}

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