128. 最长连续序列

128. 最长连续序列

function longestConsecutive(nums: number[]): number {
    const numSet = new Set(nums);
    let maxLength = 0;

    for (const num of numSet) {
        // 只有当 num 是连续序列的开头时才启动
        if (!numSet.has(num - 1)) {
            let currentNum = num;
            let length = 1;

            while (numSet.has(currentNum + 1)) {
                currentNum++;
                length++;
            }

            maxLength = Math.max(maxLength, length);
        }
    }

    return maxLength;
}```