812. Largest Triangle Area

static int wing=[]()
{
    std::ios::sync_with_stdio(false);
    cin.tie(NULL);
    return 0;
}();

class Solution 
{
public:
    double largestTriangleArea(vector<vector<int>>& points) 
    {
        double res=0;
        for(auto &i:points)
            for(auto &j:points)
                for(auto &k:points)
                    res=max(res,0.5*abs(i[0]*j[1]+j[0]*k[1]+k[0]*i[1]-j[0]*i[1]-k[0]*j[1]-i[0]*k[1]));
        return res;
    }
};

暴力解法，用了下二维平面中给出三个点坐标计算三角形面积的公式