[Solved] 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.

Question

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

Python Solution

class Solution:
    def dailyTemperatures(self, T: List[int]) -> List[int]:
        stack = []
        ans = [0]*len(T)
        for i,v in enumerate(T):
            while stack and stack[-1][1]<v:
                index,value = stack.pop()
                ans[index] = i-index
            stack.append([i,v])
        return ans