poj 2886 Who Gets the Most Candies?（线段树+反素数）

#include<iostream>
#include<cstdio>
#include<cstring>
#include<math.h>
#include<algorithm>
using namespace std;

const int INF=0x3f3f3f3f;
const int maxn=500010;
int T,n,k;
int a[maxn],loc;
char name[maxn][15];

int antiPrime[]={1,2,4,6,12,24,36,48,60,120,180,240,360,720,840,1260,1680,2520,5040,7560,10080,15120,20160,25200,27720,45360,50400,55440,83160,110880,166320,221760,277200,332640,498960,554400};
int factorNum[]={1,2,3,4,6,8,9,10,12,16,18,20,24,30,32,36,40,48,60,64,72,80,84,90,96,100,108,120,128,144,160,168,180,192,200,216};

struct segmentTree{
int l;
int r;
int v;
}node[3*maxn];

void build(int rt,int l,int r){
node[rt].l=l;
node[rt].r=r;
node[rt].v=r-l+1;
if(l==r) return ;
int mid=(l+r)>>1;
build(rt<<1,l,mid);
build(rt<<1|1,mid+1,r);
}

void Update(int rt,int pos){
node[rt].v--;
if(node[rt].l==node[rt].r){
loc=node[rt].r;
return ;
}
if(pos<=node[rt<<1].v)
Update(rt<<1,pos);
else
Update(rt<<1|1,pos-node[rt<<1].v);
}

int main(){
#ifndef ONLINE_JUDGE
freopen("test.in","r",stdin);
freopen("test.out","w",stdout);
#endif
while(~scanf("%d%d",&n,&k)){
build(1,1,n);
for(int i=1;i<=n;i++){
scanf("%s%d",name[i],&a[i]);
}
int i=0;
while(antiPrime[i]<=n)
i++;
int ansNum=factorNum[i-1];
int p=antiPrime[i-1];
while(p--){
n--;
Update(1,k);
if(!n) break;
if(a[loc]>=0)
k=(k+a[loc]-2)%n+1;
else
k=((k+a[loc]-1)%n+n)%n+1;
}
printf("%s %d\n",name[loc],ansNum);
}
return 0;
}

memset(f,0,sizeof(f));
for(int i=1;i<maxn;i++){
for(int j=0;j<maxn;j+=i){
f[j]++;
}
}
int max=0;
for(int i=1;i<maxn;i++){
if(f[i]>max){
max=f[i];
//cout<<i<<",";
cout<<f[i]<<",";
}
}