LeetCode 46 Permutations

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public static List<list <Integer>> permute(int[] nums) {
List<integer> list = new ArrayList</integer><integer>(nums.length);
List<list <Integer>> result = new ArrayList<>((int) Math.pow(2, nums.length) - 1);
boolean[] visited = new boolean[nums.length];
if (nums.length == 0) {
result.add(new ArrayList<integer>());
return result;
}
search(nums, visited, nums.length, list, result);
return result;
}
 
public static void search(int[] nums, boolean[] visited, int cur, List</integer><integer> add, List<list <Integer>> list) {
if (cur == 0) {
list.add(new ArrayList<>(add));
return;
}
for (int i = 0; i < nums.length; i++) {
if (!visited[i]) {
add.add(nums[i]);
visited[i] = true;
search(nums, visited, cur - 1, add, list);
visited[i] = false;
add.remove(add.size() - 1);
}
}
}