【Leetcode_easy】812. Largest Triangle Area

problem

812. Largest Triangle Area

solution:

class Solution {
public:
    double largestTriangleArea(vector<vector<int>>& points) {
        double res = 0.0;
        int x1=0, y1=0, x2=0, y2=0, x3=0, y3=0;
        for(int i=0; i<points.size(); ++i)
        {
            for(int j=i+1; j<points.size(); ++j)
            {
                for(int k=j+1; k<points.size(); ++k)
                {
                    x1 = points[i][0]; y1 = points[i][1];
                    x2 = points[j][0]; y2 = points[j][1];
                    x3 = points[k][0]; y3 = points[k][1];
                    double area = 0.5*abs(x1*y2+x2*y3+x3*y1-
                                          y1*x2-y2*x3-y3*x1);
                    res = max(res, area);
                }
            }
        }
        return res;
    }
};

参考

1. Leetcode_easy_812. Largest Triangle Area;

2. Grandyang;

完