java 484.查找排列（＃）。java

Posted 2021-05-08

public class Solution {
    public int[] findPermutation(String s) {
        int n = s.length(), arr[] = new int[n + 1]; 
        for (int i = 0; i <= n; i++) arr[i] = i + 1; // sorted
        for (int h = 0; h < n; h++) {
            if (s.charAt(h) == 'D') {
                int l = h;
                while (h < n && s.charAt(h) == 'D') h++;
                reverse(arr, l, h); 
            }   
        }   
        return arr;
    }   

    void reverse(int[] arr, int l, int h) {
        while (l < h) {
            int temp =  arr[l];
             arr[l] =  arr[h];
             arr[h] = temp;
            // arr[l] ^= arr[h];
            // arr[h] ^= arr[l];
            // arr[l] ^= arr[h];
            l++; h--;
        }   
    }
}