# 机器能否返回原点
# 思路： 模拟过程
public boolean judgeCircle(String moves) {
int x = 0, y = 0;
for (char i : moves.toCharArray()) {
switch (i) {
case 'U':
x++;
break;
case 'D':
x--;
break;
case 'L':
y++;
break;
case 'R':
y--;
break;
default:
break;
}
}
return x == 0 && y == 0;
}
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简化，减少判断次数。
public boolean judgeCircle(String moves) {
int[] count = new int[26];
for (char i : moves.toCharArray()) {
count[i - 'A']++;
}
return count['L' - 'A'] == count['R' - 'A'] && count['U' - 'A'] == count['D' - 'A'];
}
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