BZOJ2693: jzptab

BZOJ2693

2154 double exp啊QAQ

取模少打一个0愉快的wa一发

【代码】

#include <cstdio>#include <iostream>#include <algorithm>#define N 10000005#define INF 0x7fffffff#define mod 100000009using namespace std;typedef long long ll;typedef pair<int,int> pa;int read(){    int x=0,f=1;char ch=getchar();    while(!isdigit(ch)){if(ch=='-') f=-1;ch=getchar();}    while(isdigit(ch)){x=(x<<1)+(x<<3)+ch-'0';ch=getchar();}    return x*f;}int T,n,m;int Miu[N],p[N];ll sum[N];bool Not_Prime[N];void Get_Miu(){    Miu[1]=sum[1]=1;    for(register int i=2;i<N;i++)    {        if(!Not_Prime[i]) p[++p[0]]=i,Miu[i]=-1,sum[i]=1LL*i*(1-i);        for(register int j=1;j<=p[0]&&i*p[j]<N;j++)        {            Not_Prime[i*p[j]]=1;            if(i%p[j]!=0) Miu[i*p[j]]=-Miu[i],sum[i*p[j]]=sum[i]*sum[p[j]];            else {sum[i*p[j]]=sum[i]*p[j];break;}        }    }    for(register int i=1;i<N;i++) sum[i]=(sum[i-1]+sum[i]+mod)%mod;}ll Get_Sum(int x,int y){    return (1LL*x*(x+1)/2)%mod*((1LL*y*(y+1)/2)%mod)%mod;}int main(){    Get_Miu();    T=read();    while(T--)    {        n=read(),m=read();if(n>m) swap(n,m);        int pos;ll ans=0;        for(register int i=1;i<=n;i=pos+1)        {            pos=min(n/(n/i),m/(m/i));            ans=(ans+Get_Sum(n/i,m/i)*(sum[pos]-sum[i-1]+mod))%mod;            ans=(ans+mod)%mod;        }        printf("%lld\n",ans);    }    return 0;}