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C++
topic：657. 机器人能否返回原点 - 力扣（LeetCode）
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inspect the topic very first.
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It is letters to decide which side the robot moves. And my thought is quite sample. Assumeing the robot can move back to the origin, then the numbers of L have to be the same with the numbers of R. So are U and D.
Then the code can be easy to write. Travel through the string and count the letters.
class Solution {
public:bool judgeCircle(string moves) {int n = moves.size(); // to figure out the size at firstint countR = 0;int countL = 0;int countU = 0;int countD = 0;for (int i = 0; i < n; i++){if (moves[i] == 'R'){countR = countR + 1;}else if (moves[i] == 'L'){countL = countL + 1;}else if (moves[i] == 'U'){countU = countU + 1;}else{countD++;}}if (countR == countL && countD == countU){return true;}else{return false;}}
}; |
However, I donot think it is a elegent code. If you gays finish the Nine-year compulsory education，you will know coordinate system.
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↑ y = y + 1;
↓ y = y - 1；
← x = x - 1；
→ x = x + 1；
class Solution {
public:bool judgeCircle(string moves) {int x = 0;int y = 0;for (char c : moves) {if (c == 'U') y++;else if (c == 'D') y--;else if (c == 'R') x++;else if (c == 'L') x--;}return x == 0 && y == 0;}
}; |
It is do elegent.
Maybe apple would change the design of ios in the near future. I donot care whether the ios system is fluently or not, I just want to see what desigh looks.
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