Today I have done leetcode's November LeetCoding Challenge with cpp.

November LeetCoding Challenge 13

Description

Remove Linked List Elements

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

Solution

crab leetcode extension...

auto speedup = [](){
  cin.tie(nullptr);
  cout.tie(nullptr);
  ios::sync_with_stdio(false);
  return 0;
}();
class Solution {
public:
  vector<int> dailyTemperatures(vector<int>& temperatures) {
    vector<int> monoStack;
    int len = temperatures.size();
    vector<int> answer(len);
    for(int i = len - 1; i >= 0; --i) {
      while(monoStack.size() && temperatures[monoStack.back()] <= temperatures[i]) {
        monoStack.pop_back();
      }
      if(monoStack.size()) answer[i] = monoStack.back() - i;
      monoStack.push_back(i);
    }
    return answer;
  }
};

// Runtime: 96 ms, faster than 99.78% of C++ online submissions for Daily Temperatures.
// Memory Usage: 85 MB, less than 95.98% of C++ online submissions for Daily Temperatures.