Maximum nesting depth of the parentheses

String Stack

84.8% acceptance

Feb 25, 2026

2813

523

Given a valid parentheses string s, return the nesting depth of s. The nesting depth is the maximum number of nested parentheses.

Solution

Rust

Time O(n)

Space O(1)

LeetCode

solution.rs

impl Solution {
  pub fn max_depth(s: String) -> i32 {
    let mut depth = 0i32;
    let mut max_depth = 0i32;
    for c in s.chars() {
      if c == '(' {
        depth += 1;
        max_depth = max_depth.max(depth);
      } else if c == ')' {
        depth -= 1;
      }
    }
    max_depth
  }
}