poj1152

简单题

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

int value[300];
char st[1000000];

bool ok(int n)
{
    int len = strlen(st);
    for (int i = 0; i < len; i++)
        if (value[st[i]] >= n)
            return false;
    int temp = 0;
    int w = n - 1;
    for (int i = 0; i < len; i++)
        temp = (temp * n % w + value[st[i]] % w) % w;
    return temp == 0;
}

int main()
{
    //freopen("t.txt", "r", stdin);
    for (char ch = '0'; ch <= '9'; ch++)
        value[ch] = ch - '0';
    for (char ch = 'A'; ch <= 'Z'; ch++)
        value[ch] = ch - 'A' + 10;
    for (char ch = 'a'; ch <= 'z'; ch++)
        value[ch] = ch - 'a' + 36;
    while (scanf("%s", st) != EOF)
    {
        int ans = -1;
        for (int i = 2; i <= 62; i++)
            if (ok(i))
            {
                ans = i;
                break;
            }
        if (ans == -1)
            printf("such number is impossible!\n");
        else
            printf("%d\n", ans);
    }
    return 0;
}