Alphabet Encoding

#include <bits/stdc++.h>
using namespace std;

const int N = 100010;
char str[N];
int dp[N];

int main()
{
    scanf("%s", str+1);
    int n = strlen(str+1);
    dp[0] = 1;
    dp[1] = str[1] != '0' ? 1 : 0;
    for (int i = 2; i <= n; ++i) {
        if (str[i] != '0')
            dp[i] += dp[i-1];
        int v = (str[i-1]-'0')*10 + (str[i]-'0');
        if (v >= 10 && v <= 26)
            dp[i] += dp[i-2];
        dp[i] %= 85142019;
    }
    printf("%d\n", dp[n]);

    return 0;
}