Leetcode 594. Longest harmonious subsequence

We define a harmonious array is an array where the difference between it maximum value and its minimum value is exactly 1 .

Now, given a integer array, need to find the length of it longest harmonious subsequence among all its possible subs Equences.

Example 1:
Input: [1,3,2,2,5,2,3,7]
Output:
5

Explanation: The longest harmonious subsequence is [3,2,2,2,3].Note: The length of the input array will not exceed 20,000.

class Solution {public:    int findLHS(vector<int>& nums){ //水题        map<int, int> count;        int maxlen = 0;        for(auto o:nums)            count[o]++;        if(count.size()<=1)            return 0;        auto it1 = count.begin();        auto it2 = ++count.begin();        for(; it2!=count.end(); it1++, it2++)            if(it2->first-it1->first==1&&it1->second+it2->second>maxlen)                maxlen=it1->second+it2->second;        return maxlen;    }};

Leetcode 594. Longest harmonious subsequence