class Solution {
public:
    bool oneEditAway(string first, string second) {
        if (!first.size() && !second.size()) return true;
        if (abs<int>(first.size() - second.size()) >= 2) return false;
        if (first.size() > second.size()) swap(first, second);
        int len1 = first.size(), len2 = second.size();
        int i = 0;
        for (i = 0; i < len1; i++)
            if (first[i] != second[i]) break;
        if (i == len1) return true;
        for (len1--, len2-- ; len1 >= 0 && len2 >= 0; len1--, len2--) {
            if (first[len1] != second[len2]) break;
        }
        if (len2 - i) return false;
        return true;
    }
};