Leetcode 2147

// Leetcode 2147. Number of Ways to Divide a Long Corridor
class Solution {
public:
    int numberOfWays(string corridor) {
        string temp;
        long long output = 1;
        int count = 0;
        bool isValid = false;

        for (auto c: corridor) {
            if (c == 'S') {
                count++;
                isValid = true;
            }
            temp.push_back(c);

            if (count == 2) {
                while (count > 0) {
                    if (temp.back() == 'S') count--;
                    temp.pop_back();
                }
                temp.push_back('X');
            }
        }

        if (count || !isValid) return 0;

        while (temp.back() == 'P') temp.pop_back();

        int i = 0;
        for (; i < temp.size(); i++) {
            if (temp[i] == 'X') break;
        }

        for (; i < temp.size(); i++) {
            // count for P now
            if (temp[i] == 'P') count++;
            else {
                output *= count + 1;
                output %= 1'000'000'007;
                count = 0;
            }
        }

        return output;
    }
};