657. Judge Route Circle
nitially, 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 tothe 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: falseclass Solution { public boolean judgeCircle(String moves) { int x = 0; int y = 0; for (char ch : moves.toCharArray()) { if (ch == 'U') y++; if (ch == 'D') y--; if (ch == 'L') x--; if (ch == 'R') x++; } return x == 0 && y== 0; //检查是否回到了起点处 } }