Daily Temperatures
Problem
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 <= 10530 <= temperatures[i] <= 100
Solution
- Stack
- Time: O(n)
- Space: O(n)
class Solution(object):
def dailyTemperatures(self, temperatures):
"""
:type temperatures: List[int]
:rtype: List[int]
"""
res = [0] * len(temperatures)
stack = [] # pair: [temp, index]
for i, t in enumerate(temperatures):
while stack and t > stack[-1][0]:
stackT, stackInd = stack.pop()
res[stackInd] = (i - stackInd)
stack.append([t, i])
return res