This is a variation of the Next Greater Element problem. We use a monotonic decreasing stack to store INDICES of the temperatures. When we find a warmer day, we calculate the difference between the current index and the index at the top of the stack.

1. Initialize ans array with zeros.
2. Initialize an empty stack stack to store indices.
3. Iterate through temperatures with index i:
   • While stack is not empty and temperatures[i] > temperatures[stack[-1]]:
     • prev_index = stack.pop()
     • ans[prev_index] = i - prev_index
   • Push current index i to stack.
4. Return ans.

• Time Complexity: O(N).
• Space Complexity: O(N).

def daily_temperatures(temperatures):
    n = len(temperatures)
    ans = [0] * n
    stack = [] # Stores indices
    
    for i in range(n):
        while stack and temperatures[i] > temperatures[stack[-1]]:
            idx = stack.pop()
            ans[idx] = i - idx
        stack.append(i)
        
    return ans