Largest Triangle Area Problem & Solution
Given an array of points on the X-Y plane points where points[i] = [xi, yi], return the area of the largest triangle that can be formed by any three different points.
Answers within 10^-5 of the actual answer will be accepted.
See the largest triangle area problem on LeetCode.
C++ Solution
#pragma GCC optimize("Ofast")
#pragma GCC optimization("fast-math")
#pragma GCC optimization("unroll-loops")
#pragma GCC target("avx,avx2,fma")
static const int _=[](){std::ios::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);return 0;}();
class Solution {
public:
double largestTriangleArea(vector<vector<int>>& points) {
double largest = 0;
for (int i = 0; i < points.size() - 2; ++i) {
for (int j = i + 1; j < points.size() - 1; ++j) {
for (int k = j + 1; k < points.size(); ++k) {
double area = abs(0.5 * (points[i][0] * (points[j][1] - points[k][1]) + points[j][0] * (points[k][1] - points[i][1]) + points[k][0] * (points[i][1] - points[j][1])));
largest = max(largest, area);
}
}
}
return largest;
}
};