Link/Cut Tree（大数）

Programmer Rostislav got seriously interested in the Link/Cut Tree data structure, which is based on Splay trees. Specifically, he is now studying the expose procedure.

Unfortunately, Rostislav is unable to understand the definition of this procedure, so he decided to ask programmer Serezha to help him. Serezha agreed to help if Rostislav solves a simple task (and if he doesn’t, then why would he need Splay trees anyway?)

Given integers l, r and k, you need to print all powers of number k within range from l to r inclusive. However, Rostislav doesn’t want to spent time doing this, as he got interested in playing a network game called Agar with Gleb. Help him!
Input

The first line of the input contains three space-separated integers l, r and k (1 ≤ l ≤ r ≤ 1018, 2 ≤ k ≤ 109).
Output

Print all powers of number k, that lie within range from l to r in the increasing order. If there are no such numbers, print “-1” (without the quotes).
Example
Input

1 10 2

Output

1 2 4 8

Input

2 4 5

Output

-1

Note

Note to the first sample: numbers 20 = 1, 21 = 2, 22 = 4, 23 = 8 lie within the specified range. The number 24 = 16 is greater then 10, thus it shouldn’t be printed.

#include <iostream>
#include <cstdio>
using namespace std;
int main()
{
    long long int a, b, k;
    scanf("%lld %lld %lld", &a, &b, &k);
    long long int m = 1;
    int ans = 0;
    while(m<=b)
    {
        if(m>=a)
            {
                cout<<m<<' ';
                ans++;
            }
            if(b/m<k)//限制条件，否则可能会有更大的数出现，存不下
            break;
            m = m * k;
    }
    if(ans==0)
        cout<<-1<<endl;
    else
        cout<<endl;
    return 0;
}