Poj2033

#include <cstdio>
#include <algorithm>
#include <cstring>
#include <iostream>
#define LL  long long
const int MAXN = 50100;
using namespace std;
char str[MAXN];
LL dp[MAXN];
int main()
{
    while(gets(str+1)) {
        int len = strlen(str+1);
        if(str[1] == ‘0‘ && len == 1) {
            break;
        }
        dp[0] = dp[1] = 1;
        for(int i = 2; i <= len; ++i) {
            if(str[i] != ‘0‘) {
                  dp[i] = dp[i-1];
                  int num = (str[i-1] -‘0‘) * 10 + str[i] - ‘0‘;
                  if(num >= 11 && num <= 26)
                        dp[i] += dp[i-2];
            } else {
                  if(str[i-1] == ‘0‘)
                        dp[i] = dp[i-1];
                  else if(str[i-1] == ‘1‘ || str[i-1] == ‘2‘)
                        dp[i] = dp[i-2];
            }
        }
        cout << dp[len] << endl;
      }
    return 0;
}