LeetCode-Java-657. Judge Route Circle

题目

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

用图形思维考虑代码

class Solution {
    public boolean judgeCircle(String moves) {
        int x=0,y=0;
        int len = moves.length();
        for(char temp : moves.toCharArray()){
                switch(temp)
                {
                    case 'U':
                        y++;
                        break;
                    case 'D':
                        y--;
                        break;
                    case 'R':
                        x++;
                        break;
                    case 'L':
                        x--;
                        break;
                }

        }
        return x==0&&y==0;
    }
}