Question

How to check if a string contains only valid parentheses (open close same type (), {}, []) in Node.js

Answer 1

class Program {
    string_contains_valid_parentheses(s) {
        const arr = [];
        for (const ch of s) {
            if (ch === '(') {
                arr.push(')');
            }
            else if (ch === '{') {
                arr.push('}');
            }
            else if (ch === '[') {
                arr.push(']');
            }
            else if (arr.length === 0 || this.pop(arr) !== ch) {
                return false;
            }
        }
        return arr.length === 0;
    }
    pop(arr) {
        const ch = arr.pop();
        return ch;
    }
}
 
const p = new Program();
 
console.log(p.string_contains_valid_parentheses("(){}[]()()(){}"));
 
 
 
 
/*
run:
 
true
 

*/

 

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