Leetcode049--最長連續子數組

一、原題

Given an unsorted array of integers, find the length of the longest consecutive elements sequence.

For example,
Given[100, 4, 200, 1, 3, 2],
The longest consecutive elements sequence is[1, 2, 3, 4]. Return its length:4.

Your algorithm should run in O(n) complexity.

一、中文

給出一個數組，求出裏面能夠組成的最長連續子數組的長度並返回

三、舉例

比如數組[100, 4, 200, 1, 3, 2]中的最長子數組的長度就是[1, 2, 3, 4]

四、思路

首先對數組進行排序，然後將排序後的數組進行查找，從最左邊開始，如果相鄰就加一，如果不相鄰就將其置零

五、程序

import java.util.*;

public class Solution {
    //發現連續的子字符串
    public int longestConsecutive(int[] num) {
        //排序
        Arrays.sort(num);
        
        int max = 1;
        int count = 1;
        for(int i = 1; i < num.length; i++){
            if((num[i] - num[i-1]) == 1){
                count++;
                if(count > max){
                    max = count;
                }
            }else if(num[i] - num[i-1] == 0){
                continue;
            }else{
                count = 1;
            }
            
        }
        return max;
    }
}