剑指 Offer II 038. 每日温度

自己想的这个 时间、空间上都很低 = = 。。 无语

截屏2022-04-20 上午10.03.12.png

func dailyTemperatures(_ temperatures: [Int]) -> [Int] {

        var day = 0
        var array = Array<Int>()
        let len = temperatures.count
        for i in 0..<(len - 1){
            
            let num1 = temperatures[i]
            day = 0
            var exit = false
            for j in (i+1)..<len {
                
                let num2 = temperatures[j]
                day += 1
                if num2 > num1 {
                    exit = true
                    array.append(day)
                    break
                }
            }
            if !exit {
                array.append(0)
            }
            
        }
        array.append(0)
        return array
    }

然后就是单调栈了。。 还挺奇妙的。。

   func dailyTemperatures(_ temperatures: [Int]) -> [Int] {

            let len = temperatures.count
            if len == 1 {
                return [0]
            }

            var array = Array<Int>(repeating: 0, count: len)
            var stack = Array<Int>()
            var i = 0
            while( i < temperatures.count){
                if stack.isEmpty || temperatures[i] <= temperatures[stack.last!]{
                    stack.append(i)
                    i += 1

                }
                else {
                    let index = stack.popLast()!
                    array[index] = i - index
                }
                
            
            
            }
            
            return array
        }