bzoj3529【線性篩】【莫比烏斯函數】【樹狀數組】

#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstdlib>
#include<cstring>
using namespace std;
#define pii pair<int,int>
#define fi first
#define se second
typedef long long LL;
inline int read()
{
	int x=0;bool f=0;char c=getchar();
	for (;c<'0'||c>'9';c=getchar()) f=c=='-'?1:0;
	for (;c>='0'&&c<='9';c=getchar()) x=x*10+c-'0';
	return f?-x:x;
}
const int N=100000,M=N+10,mod=(1<<31)-1;
int q,pr[M],pc=0,mu[M],mp[M],mps[M],ans[20010],ss[M];
pii f[M];bool np[M];
struct na
{
	int n,m,a,id;
}e[20010];

inline bool cmp(const na &a,const na &b)
{
	return a.a<b.a;
}

inline void add(int x,int a)
{
	for (;x<=N;x+=x&-x) ss[x]+=a;
}

inline int cal(int x)
{
	int rec=0;
	for (;x;x-=x&-x) rec+=ss[x];
	return rec;
}

int query(int n,int m)
{
	int rec=0;if (n>m) swap(n,m);
	for (int i=1,pos;i<=n;i=pos+1)
	{
		pos=min(n/(n/i),m/(m/i));
		rec+=(cal(pos)-cal(i-1))*(n/i)*(m/i);
	}
	rec&=mod;
	return rec;
}

int main()
{
	for (int i=2;i<=N;i++)
	{
		if (!np[i]) pr[++pc]=i,mu[i]=-1,mp[i]=i,f[i].fi=mps[i]=i+1;
		for (int j=1,k=i<<1;j<=pc&&k<=N;k=i*pr[++j])
		{
			np[k]=1;
			if (i%pr[j]==0) 
			{
				mu[k]=0;
				f[k].fi=f[i].fi/mps[i];
				mps[k]=mps[i]+(mp[k]=mp[i]*pr[j]);
				f[k].fi*=mps[k];
				break;
			}
			mu[k]=-mu[i];
			mp[k]=pr[j];mps[k]=pr[j]+1;
			f[k].fi=f[i].fi*mps[k];
		}
	}
	f[1].fi=1;mu[1]=1;
	for (int i=1;i<=N;i++) f[i].se=i;
	sort(f+1,f+N+1);
	q=read();
	for (int i=1;i<=q;i++)
		e[i].n=read(),e[i].m=read(),e[i].a=read(),e[i].id=i;
	sort(e+1,e+q+1,cmp);
	for (int i=1,j=1;j<=q;j++)
	{
		for (;i<=N&&f[i].fi<=e[j].a;i++)
			for (int k=f[i].se;k<=N;k+=f[i].se)
				add(k,f[i].fi*mu[k/f[i].se]);
		ans[e[j].id]=query(e[j].n,e[j].m);
	}
	for (int i=1;i<=q;i++) printf("%d\n",ans[i]);
	return 0;
}