poj 2545 Hamming Problem

Hamming Problem

Time Limit: 1000MS		Memory Limit: 65536K
Total Submissions: 5626		Accepted: 2528

Description

For each three prime numbers p1, p2 and p3, let's define Hamming sequence Hi(p1, p2, p3), i=1, ... as containing in increasing order all the natural numbers whose only prime divisors are p1, p2 or p3.

For example, H(2, 3, 5) = 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 16, 18, 20, 24, 25, 27, ...

So H5(2, 3, 5)=6.

Input

In the single line of input file there are space-separated integers p1 p2 p3 i.

Output

The output file must contain the single integer - Hi(p1, p2, p3). All numbers in input and output are less than 10^18.

Sample Input

7 13 19 100

Sample Output

26590291

#include<iostream>
using namespace std;

__int64 mini(__int64 a,__int64 b)
{
    if(a<b)
        return a;
    return b;
}

int main()
{
    __int64 p1,p2,p3,ii;
    int i,j,k;
    int p;
    __int64 res[100000];
    __int64 resi,resj,resk;
    while(scanf("%I64d %I64d %I64d %I64d",&p1,&p2,&p3,&ii)!=EOF)
    {
        i=0;j=0;k=0;
        res[0]=1;
        p=1;
        while(p<=ii)
        {
            resi=res[i]*p1;
            resj=res[j]*p2;
            resk=res[k]*p3;
            res[p]=mini(mini(resi,resj),resk);
            if(res[p]==resi)i++;
            if(res[p]==resj)j++;
            if(res[p]==resk)k++;
            p++;
        }
        printf("%I64d\n",res[ii]);
    }
    return 0;
}