leetcode 657. Judge Route Circle

Initially, there is a Robot at position (0, 0). Given a sequence of its moves, judge if this robot makes a circle, which means it moves back to the original place.

The move sequence is represented by a string. And each move is represent by a character. The valid robot moves are R (Right), L(Left), U (Up) and D (down). The output should be true or false representing whether the robot makes a circle.

Example 1：

Input: "UD"
Output: true

Example 2:

Input: "LL"
Output: false

代码：

class Solution {
    public boolean judgeCircle(String moves) {
        int x=0;
        int y=0;
        for(int i=0;i<moves.length();i++){
           char c=moves.charAt(i);
            switch(c){
                case 'U':
            x++;
                    break;
                case 'D':
            x--;
                    break;
                case 'R':
            y++;
                    break;
                case 'L':
            y--;
                    break;
            }
           
            
        }
         if ((x==0)&&(y==0)){return true;}
            else 
            return false;
         
    }
}