class Solution { func dailyTemperatures(_ temperatures: [Int]) -> [Int] { var result = [Int](repeating: 0, count: temperatures.count) var st: [Int] = [] for (i, t) in temperatures.enumerated() { while !st.isEmpty && temperatures[st.last!] < t { result[st.last!] = i - st.last! st.removeLast() } st.append(i) } return result } }