Leetcode题解-657. Judge Route Circle

Leetcode题解-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

思路

这道题很简单，发现规律，只有当U和D操作次数相同且L和R的操作次数也相同时才能回到原点

代码

bool judgeCircle(string moves) {        int vertical = 0, horizen = 0;        int l = moves.size();        for(int i = 0; i < l; i++){            switch(moves[i]){                case 'U':                    vertical++;                    break;                case 'D':                    vertical--;                    break;                case 'L':                    horizen++;                    break;                case 'R':                    horizen--;                    break;                default:;            }        }         return ((!horizen) && (!vertical));    }