和最小的LCM (Minimum Sum LCM, UVa 10791)

#include <iostream>
#include <string.h>
#include <string>
#include <fstream>
#include <algorithm>
#include <stdio.h>
#include <vector>
#include <queue>
#include <set>
#include <cmath>
using namespace std;
const double eps = 1e-8;
const int INF=0x7fffffff;
unsigned long long uINF = ~0LL;
#define MAXN 10000007
typedef long long LL;
LL vis[MAXN];
LL prime[MAXN];

void sieve(LL n)
{
    LL m=(LL)sqrt(n+0.5);
    memset(vis,0,sizeof(vis));
    for(LL i=2;i<=m;i++)if(!vis[i])
    for(LL j=i*i;j<=n;j+=i)vis[j]=1;
}

LL gen_prime(LL n)
{
    sieve(n);
    LL c=0;
    for(LL i=2;i<=n;i++)if(!vis[i])
        prime[c++]=i;
    return c;
}

LL gcd(LL a,LL b)
{
    return b==0?a:gcd(b,a%b);
}

LL solve(LL n)
{
    LL flag=0,np=0;
    LL temp=n,sum=0,num;
    for(LL i=2;i*i<=temp;i+=2)
    {
        //cout<<i<<' ';
        num=1;
        while(temp%i==0)
        {
            if(num==1)flag++;
            temp/=i;num*=i;
        }
        if(num==1)num=0;
        sum+=num;
        if(i==2)i--;
        np++;
    }
    if(temp>1){flag++;sum+=temp;}
    if(flag==0||flag==1)sum=n+1;
    return sum;
}

int main()
{
    LL t=1;
    LL n;
    while(scanf("%lld",&n),n)
    {
        printf("Case %lld: %lld
",t++,solve(n));
    }

    return 0;
}

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