class Solution {
public int getTranslationCount(String s) {
//f[i] = f[i - 1] + f[i-2](1<=s[i-1]s[i] < 26)
int[] f = new int[s.length() + 1];
f[1] = 1;
f[0] = 1;
for(int i = 2; i <= s.length(); i++) {
f[i] = f[i-1];
if(s.charAt(i-2) == '1' || s.charAt(i - 2) == '2' && s.charAt(i-1) < '6') {
f[i] += f[i-2];
}
}
return f[s.length()];
}
}