Mono-descreasing stack⌗ 

class Solution {
public:
	vector<int> dailyTemperatures(vector<int>& temperatures) {
		vector<int> res(temperatures.size(), 0);
		stack<int> st;
		for (int i = 0; i < temperatures.size(); i++) {
			while (!st.empty() && temperatures[st.top()] < temperatures[i]) {
				res[st.top()] = i - st.top();
				st.pop();
			}
			st.push(i);
		}
		return res;
	}
};

[73,74,75,71,69,72,76,73]