Valid parentheses

Hard 40 pts New · no attempts yet javascript

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Check if "([]){}" has balanced brackets.

Static hints

Use a stack; push open brackets, pop on close.

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const s = "([]){}";
const stack = [];
const pairs = { ")": "(", "]": "[", "}": "{" };
for (const ch of s) {
  if ("([{".includes(ch)) stack.push(ch);
  else if (stack.pop() !== pairs[ch]) { console.log(false); process.exit(0); }
}
console.log(stack.length === 0);

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Explanation

Stack-based bracket matching—top FAANG interview question.

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Valid parentheses

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