var isValid = function (s) {

const openers = ["{", "[", "("],

closers = ["}", "]", ")"];

const map = new Map([

["{", "}"],

["(", ")"],

["[", "]"],

]);

let stack = [];

for (const i of s) {

// for present letter (

// it is present in the opener, we push it in stack

if (openers.includes(i)) stack.push(i);

// then for the next letter ), if its in closer array

else if (closers.includes(i)) {

// pop the previous inserted letter from the stack

let prev = stack.pop();

//searching the pop letter '(' in map which return us with ')'

//if the ')' matches with the presnet letter which is also ')' return true

if (map.get(prev) !== i) return false;

}

}

console.log(stack.length === 0);

return stack.length === 0;

};

console.log(isValid("()"));

console.log(isValid("(]"));

console.log(isValid("(){}}{"));