BZOJ2693: jzptab

【代码】

#include <cstdio>
#include <iostream>
#include <algorithm>
#define N 10000005
#define INF 0x7fffffff
#define mod 100000009
using 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
,p
;
ll sum
;
bool Not_Prime
;

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;
}