Leet Code Weekly Contest 277

class Solution
{
public:

    int countElements(vector<int>& nums)
    {
        int a = INT_MAX, b = INT_MIN;
        
        for (auto &x : nums)
        {
            a = min(a, x);
            b = max(b, x);
        }
        
        int ans = 0;
        
        for (auto &x : nums)
        {
            if (x > a && x < b)
            {
                ans++;
            }
        }
        
        return ans;
    }
};

class Solution
{
public:
    
    vector<int> rearrangeArray(vector<int>& nums)
    {
        vector<int> a, b;
        
        for (auto &x : nums)
        {
            if (x > 0)
            {
                a.push_back(x);
            }
            else
            {
                b.push_back(x);
            }
        }
        
        vector<int> ans;
        
        for (int i = 0, j = 0; i < a.size() || j < b.size(); )
        {
            if (i < a.size())
            {
                ans.push_back(a[i++]);
            }
            
            if (j < b.size())
            {
                ans.push_back(b[j++]);
            }
        }
        
        return ans;
    }
};

class Solution {
public:
    
    vector<int> findLonely(vector<int>& nums)
    {
        unordered_map<int, int> cnt;
        
        for (auto &x : nums)
        {
            if (cnt.find(x) == cnt.end())
            {
                cnt[x] = 0;
            }
            
            cnt[x]++;
        }
        
        vector<int> ans;
        
        for (auto &x : nums)
        {
            if (cnt[x] == 1 && cnt.find(x + 1) == cnt.end() && cnt.find(x - 1) == cnt.end())
            {
                ans.push_back(x);
            }
        }
        
        return ans;
    }
};

class Solution {
public:
    
    int maximumGood(vector<vector<int>>& statements)
    {
        int n = statements.size();
        
        int ans = 0;
        
        bool t[16];
        
        for (int mask = 0; mask < (1 << n); mask++)
        {
            for (int i = 0; i < n; i++)
            {
                t[i] = (mask & (1 << i)) > 0;
            }
            
            bool valid = true;
            
            for (int i = 0; i < n && valid; i++)
            {
                for (int j = 0; j < n && valid; j++)
                {
                    if (statements[i][j] == 2)
                    {
                        continue;
                    }
                    
                    bool s = statements[i][j] == 1;
                    
                    if (t[i] && s != t[j])
                    {
                        valid = false;
                    }
                }
            }
            
            if (valid)
            {
                int cnt = 0;
                
                for (int i = 0; i < n; i++)
                {
                    if (t[i])
                    {
                        cnt++;
                    }
                }
                
                ans = max(ans, cnt);
            }
        }
        
        return ans;
    }
};