問題描述
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
Input: "UD"
Output: true
Input: "LLRUDRR"
Output: false
思路：設(shè)置兩個(gè)計(jì)數(shù)器九孩，根據(jù)走的路線來判斷是++還是--嫩挤，最后都為0則回到原點(diǎn)
* @param {string} moves
* @return {boolean}
*/
var judgeCircle = function(moves) {
var x = 0;
var y = 0;
for(var i = 0; i < moves.length; i++){
if(moves.charAt(i) === 'R'){
x++;
}
if(moves.charAt(i) === 'L'){
x--;
}
if(moves.charAt(i) === 'U'){
y++;
}
if(moves.charAt(i) === 'D'){
y--;
}
}
if( x===0 && y===0){
return true;
}
else{return false;}
};
