目录

• notes
  • java switch 语句
  • java api: array 直接有 length 属性 ，不必：length()
  • sol 657

0204 需要完成的

? 657. 机器人能否返回原点

https://leetcode-cn.com/problems/robot-return-to-origin/

? 1299. 将每个元素替换为右侧最大元素

https://leetcode-cn.com/problems/replace-elements-with-greatest-element-on-right-side/

? 1051 高度检查器

https://leetcode-cn.com/problems/height-checker

? 728 自除数

https://leetcode-cn.com/problems/self-dividing-numbers

? 104 二叉树的最大深度

https://leetcode-cn.com/problems/maximum-depth-of-binary-tree

notes

java switch 语句

switch(expression){
    case value :
       //语句
       break; //可选
    case value :
       //语句
       break; //可选
    //你可以有任意数量的case语句
    default : //可选
       //语句
}

java api: array 直接有 length 属性 ，不必：length()

sol 657

class Solution {
    public boolean judgeCircle(String moves) {
        char [] allMovesSplited = moves.toCharArray();
        int len = allMovesSplited.length;
        int i = 0;
        int x = 0;
        int y = 0;
        while(i < len) {
            switch(allMovesSplited[i]) {
                case 'U':
                    y++;
                    break;
                case 'D':
                    y--;
                    break;
                case 'L':
                    x--;
                    break;
                case 'R':
                    x++;
                    break;
                default:
                    break;
            }
            i++;
        }
        return x==0 && y==0;
    }
}
//or
class Solution {
    public boolean judgeCircle(String moves) {
        int col = 0, row = 0;
        for(char ch : moves.toCharArray()){
            if(ch == 'U') row++;
            else if(ch == 'D') row--;
            else if(ch == 'L') col--;
            else col++;
        }
        return col == 0 && row == 0;
    }
}

原文地址：https://www.cnblogs.com/paulkg12/p/12258422.html