LeetCodeDaily/1106. Parsing A Boolean Expression at main · Tutul-dhar/LeetCodeDaily · GitHub

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class Solution {
public:
    bool parseBoolExpr(string expression) {
        stack<char> q,qq;
        for(char ch : expression) {
            if(ch == ',') continue;
            if(ch == '(' or ch == 'f' or ch == 't') q.push(ch);
            else if(ch == ')') {
                int cntTrue = 0,cntFalse = 0;
                while(q.size() and q.top() != '(') {
                    if(q.top() == 'f') cntFalse++;
                    else cntTrue++;
                    q.pop();
                }
                q.pop();
                char ch1 = qq.top();
                qq.pop();
                if(ch1 == '|') {
                    if(cntTrue) q.push('t');
                    else q.push('f');
                } else if(ch1 == '&') {
                    if(cntFalse) q.push('f');
                    else q.push('t');
                } else {
                    if(cntFalse) q.push('t');
                    else q.push('f');
                }
            } else qq.push(ch);
        }

        if(q.top() == 't') return true;
        return false;
    }
};