[leetcode] 46. Permutations

문제(DFS)

Given an array nums of distinct integers, return all the possible permutations. You can return the answer in any order.

Constraints

• 1 <= nums.length <= 6
  시간 복잡도 6!
• 10 <= nums[i] <= 10
  int안에 다 들어가는 범위
• All the integers of nums are unique.
  똑같은 수 x

정답

var permute = (nums) => {
    const result = [];
    const current = [];

    backtracking(nums, result, current);
    console.log(result);
};

const backtracking = (nums, result, current) => {
    if (nums.length == current.length) {
        result.push(Array.from(current));
        return;
    }

    for (let i = 0; i < nums.length; i++) {
        if (current.includes(nums[i])) continue;
        current.push(nums[i]);
        backtracking(nums, result, current);
        current.pop();
    }
}

permute([1, 2, 3]);  

Review

1. 문제를 안읽고 input output값만 보고 문제를 풀려했었다.
2. 조건은 안읽었다.