Create 812. Largest Triangle Area (#898)

Author: Chayandas07

812. Largest Triangle Area

@@ -0,0 +1,19 @@
+class Solution {
+public:
+    double largestTriangleArea(vector<vector<int>>& points) {
+        double max_area = 0.0;
+        int n = points.size();
+        for (int i = 0; i < n; ++i) {
+            for (int j = i + 1; j < n; ++j) {
+                for (int k = j + 1; k < n; ++k) {
+                    int x1 = points[i][0], y1 = points[i][1];
+                    int x2 = points[j][0], y2 = points[j][1];
+                    int x3 = points[k][0], y3 = points[k][1];
+                    double area = 0.5 * abs(x1*(y2 - y3) + x2*(y3 - y1) + x3*(y1 - y2));
+                    max_area = max(max_area, area);
+                }
+            }
+        }
+        return max_area;
+    }
+};