poj2591

暴力做就可以过。

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
using namespace std;

#define maxn 10000005

int ans[maxn];

int main()
{
//    freopen("t.txt", "r", stdin);
    int p1, p2;
    ans[0] = 1;
    p1 = 0;
    p2 = 0;
    for (int i = 1; i <= 10000000; i++)
    {
        ans[i] = min(ans[p1] * 2 + 1, ans[p2] * 3 + 1);
        if (ans[i] == ans[p1] * 2 + 1)
            p1++;
        if (ans[i] == ans[p2] * 3 + 1)
            p2++;
    }
    int n;
    while (scanf("%d", &n) != EOF)
        printf("%d\n", ans[n - 1]);
    return 0;
}