Daily Temperatures

Given a list of daily temperatures T, return a list such that, for each day in the input, tells you how many days you would have to wait until a warmer temperature. If there is no future day for which this is possible, put 0 instead.

For example, given the list of temperatures T = [73, 74, 75, 71, 69, 72, 76, 73], your output should be [1, 1, 4, 2, 1, 1, 0, 0].

Note: The length of temperatures will be in the range [1, 30000]. Each temperature will be an integer in the range [30, 100].

class Solution {
    public int[] dailyTemperatures(int[] T) {
        // Using deque as a stack
        // Because deque is faster than stacks and queues
        Deque<Integer> st = new LinkedList<>();
        int[] ans = new int[T.length];
        for (int i = T.length - 1; i >= 0; i--) {
            while (st.size() > 0 && T[st.peekFirst()] <= T[i])
                st.pollFirst();
            if (st.size() == 0)
                ans[i] = 0;
            else
                ans[i] = st.peek() - i;
            st.addFirst(i);
        }
        return ans;
    }
}