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function isValid(s) {
JavaScript · leetcode · type the snippet below to practice
def fib(n):
a, b = 0, 1
for _ in range(n):
a, b = b, a + b
return a
about this snippet
This is the validparens snippet in JavaScript — a classic LeetCode interview problem. Type it through to build the muscle memory you need to write it under interview pressure. DeveloperType scores you on net WPM and accuracy and only counts runs above 95% accuracy on the leaderboard, so practice rewards precision, not speed alone.
view source (13 lines)
function isValid(s) {
const stack = [];
const pairs = { ")": "(", "]": "[", "}": "{" };
for (const c of s) {
if (c in pairs) {
if (stack.pop() !== pairs[c]) return false;
} else {
stack.push(c);
}
}
return stack.length === 0;
}
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