[LeetCode] 657. Judge Route Circle

轉自LeetCode

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

<Solution>

想法如下

• 這題不難，歷遍一次字串，移動座標，最後檢查是不是在原點就好

code 如下

Java

	class Solution {
	public boolean judgeCircle(String moves) {
	int x = 0, y = 0;
	for(char c : moves.toCharArray()) {
	if(c == 'U') {
	++y;
	}
	else if(c == 'D') {
	--y;
	}
	else if(c == 'L') {
	--x;
	}
	else {
	++x;
	}
	}
	return x == 0 && y == 0;
	}
	}

view raw judgeCircle.java hosted with ❤ by GitHub