uva 11099

這題難，用篩子法並且強化，把每個number的質因數相乘之後做排序，就可以得知下一個順序是哪位

 

2 4 8 16 32 ........3 6 9

所以如果下一個的質因數相乘不是上一個的話，就代表已經超過MAX範圍了

//============================================================================
// Name        : Next Same-Factored.cpp
// Date : 2013/3/30 上午12:42:53
// Author : GCA
//============================================================================
#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <climits>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <cctype>
#include <utility>
using namespace std;
#ifdef ONLINE_JUDGE
#define ll "%lld"
#else
#define ll "%I64d"
#endif
typedef unsigned int uint;
typedef long long int Int;
#define Set(a,s) memset(a,s,sizeof(a))
#define Write(w) freopen(w,"w",stdout)
#define Read(r) freopen(r,"r",stdin)
#define Pln() printf("\n")
#define I_de(x,n)for(int i=0;i<n;i++)printf("%d ",x[i]);Pln()
#define De(x)printf(#x"%d\n",x)
#define For(i,x)for(int i=0;i<x;i++)
#define CON(x,y) x##y
#define Pmz(dp,nx,ny)for(int hty=0;hty<ny;hty++){for(int htx=0;htx<nx;htx++){\
    printf("%d ",dp[htx][hty]);}Pln();}
#define M 2000001
#define PII pair<int,int>
#define PB push_back
#define oo INT_MAX
#define Set_oo 0x3f
#define Is_debug true
#define debug(...) if(Is_debug)printf("DEBUG: "),printf(__VA_ARGS__)
#define FOR(it,c) for(__typeof((c).begin()) it=(c).begin();it!=(c).end();it++)
#define eps 1e-6
bool xdy(double x,double y){return x>y+eps;}
bool xddy(double x,double y){return x>y-eps;}
bool xcy(double x,double y){return x<y-eps;}
bool xcdy(double x,double y){return x<y+eps;}
int min3(int x,int y,int z){
    int tmp=min(x,y);
    return min(tmp,z);
}
int max3(int x,int y,int z){
    int tmp=max(x,y);
    return max(tmp,z);
}
struct nums{
    int primesum;
    int all;
    int tmp;
}num[M];
int sid[M];
bool cmp(nums a,nums b){
    if(a.primesum<b.primesum){
        return true;
    }else if(a.primesum>b.primesum){
        return false;
    }else{
        return a.all<b.all;
    }
}
int main() {
    ios_base::sync_with_stdio(0);
    for(int i=0;i<M;i++){
        num[i].tmp=num[i].all=i;
        num[i].primesum=1;
    }
    for(int i=2;i<M;i++){
        if(num[i].all==num[i].tmp){
            num[i].primesum=i;
            for(int prime=(i<<1);prime<M;prime+=i){
                num[prime].primesum*=i;
                num[prime].tmp/=i;
            }
        }
    }
    sort(num,num+M,cmp);
    for(int i=0;i<M;i++){
        sid[num[i].all]=i;
//        debug("%d",num[i].all);
    }
    int n;
    while(~scanf("%d",&n)){
        if(n==0||n==1){
            puts("Not Exist!");
            continue;
        }
        n=sid[n];
//        debug("%d",num[n+1].all);
        if(num[n].primesum==num[n+1].primesum){
            if(num[n+1].all<=2000000)
                printf("%d\n",num[n+1].all);
            else puts("Not Exist!");
        }else puts("Not Exist!");
    }
















}