hdu4944与因子有关

#include<cstdio>#include<iostream>using namespace std;#define ll long longconst int need_num=500000;const int max_n=500000+100;const ll mod=1ll<<32;ll f[max_n];void init(){    f[1]=1;    for(int i=2;i<=need_num;i++)    {        f[i]=f[i-1];        ll cur=0;        for(int j=1;j*j<=i;j++)            if(i%j==0)            {                cur+=(j+1)*j/2;                if(j*j==i)break;                ll k=i/j;                cur+=(k+1)*k/2;            }        cur%=mod;        f[i]=(f[i]+cur*i%mod)%mod;    }}int main(){    init();    int T;    cin>>T;    for(int cas=1;cas<=T;cas++)    {        int n;        scanf("%d",&n);        printf("Case #%d: %I64d\n",cas,f[n]);    }    return 0;}