682. 棒球比赛

Posted 2022-03-28 心脏dance

题目链接：力扣

思路：用栈来模拟操作就可以了。注意：留意下 “+” 的操作。

上代码：

class Solution 
    fun calPoints(ops: Array<String>): Int 
        val mStack = Stack<Int>()
        var result = 0
        ops.forEach  str ->
            when (str) 
                "+" -> 
                    val tmp1 = mStack.pop()
                    val tmp2 = mStack.pop()
                    mStack.push(tmp2)
                    mStack.push(tmp1)
                    mStack.push(tmp1 + tmp2)
                
                "D" -> mStack.push(mStack.peek() * 2)
                "C" -> mStack.pop()
                else -> mStack.push(str.toInt())
            
        
        while (mStack.isNotEmpty()) 
            result += mStack.pop()
        
        return result
    

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