[leetcode] 41. First Missing Positive 풀이

[leetcode] 41. First Missing Positive 힌트

var firstMissingPositive = function(nums) {
    const n = nums.length;

    for (let i = 0; i < n; i++) {
        if (nums[i] <= 0) {
            nums[i] = n + 1;
        }
    }

    nums.sort((a, b) => a - b);

    for (let i = 0; i < n; i++) {
        const next = nums[i + 1];

        if (nums[i] === next) {
            nums[i] = n + 1;
        }
    }

    nums.sort((a, b) => a - b);

    let num = 1;

    for (let i = 0; i < n; i++) {
        if (nums[i] !== num) {
            return num;
        }

        num++;
    }

    return n + 1;
};