[leetcode] 739. Daily Temperatures

 

 

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

 

class Solution(object):
    def dailyTemperatures(self, temperatures):
        """
        :type temperatures: List[int]
        :rtype: List[int]
        """
        answer = [0] * len(temperatures)
        stack = [] 
        
        for i, cur in enumerate(temperatures):
            
            while stack and cur > temperatures[stack[-1]]: 
                last = stack.pop()
                answer[last] = i - last 
            
            stack.append(i)
        return answer