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| class Solution {
public:
int cross(int x1,int y1,int x2,int y2){
return x1 * y2 - x2 * y1;
}
double area(int a,int b,int c,int d,int e,int f){
double sum = 0;
sum += cross(a,b,c,d);
sum += cross(c,d,e,f);
sum += cross(e,f,a,b);
return abs(sum / 2.0);
}
double largestTriangleArea(vector<vector<int>>& points) {
int n = points.size();
double ans = 0;
for(int i = 0;i < n;i++){
for(int j = i + 1;j < n;j++){
for(int p = j + 1;p < n;p++){
ans = max(ans,area(points[i][0],points[i][1]
,points[j][0],points[j][1]
,points[p][0],points[p][1]));
}
}
}
return ans;
}
};
|