Daily temperatures

Array Stack Monotonic Stack

68.4% acceptance

Feb 21, 2026

14581

372

Given an array of integers temperatures represents the daily temperatures, return an array answer such that answer[i] is the number of days you have to wait after the ith day to get a warmer temperature. If there is no future day for which this is possible, keep answer[i] == 0 instead.

Solution

Rust

Time O(n²)

Space O(n)

LeetCode

solution.rs

/*
 * Given an array of integers temperatures represents the daily temperatures, return an array answer such that answer[i] is the number of days you have to wait after the ith day to get a warmer temperature. If there is no future day for which this is possible, keep answer[i] == 0 instead.
 * Example 1:
 * Input: temperatures = [73,74,75,71,69,72,76,73]
 * Output: [1,1,4,2,1,1,0,0]
 * Example 2:
 * Input: temperatures = [30,40,50,60]
 * Output: [1,1,1,0]
 * Example 3:
 * Input: temperatures = [30,60,90]
 * Output: [1,1,0]
 * Constraints:
 * 1 <= temperatures.length <= 105
 * 30 <= temperatures[i] <= 100
 */
impl Solution {
  pub fn daily_temperatures(temperatures: Vec<i32>) -> Vec<i32> {
    let n = temperatures.len();
    let mut ans = vec![0i32; n];
    let mut stack: Vec<usize> = vec![];
    for i in 0..n {
      while let Some(&top) = stack.last() {
        if temperatures[i] > temperatures[top] {
          stack.pop();
          ans[top] = (i - top) as i32;
        } else {
          break;
        }
      }
      stack.push(i);
    }
    ans
  }
}