Find Centroid of a Triangle in C++

In this problem, we are given a 2D array that denotes coordinates of three vertices of the triangle. Our task is to create a program to find the Centroid of the Triangle in C++.

Centroid of a triangle is the point at which the three medians of the triangles intersect.

Median of a triangle is the line that connects the vertex of the triangle with the center point of the line opposite to it.

Let’s take an example to understand the problem,

Input

(-3, 1), (1.5, 0), (-3, -4)

Output

(-3.5, -1)

Explanation

Centroid (x, y) = ((-3+2.5-3)/3, (1 + 0 - 4)/3) = (-3.5, -1)

Solution Approach

For solving the problem, we will use the geometrical formula for the centroid of the triangle.

For points (ax, ay), (bx, by), (cx, cy)

Centroid, x = (ax + bx + cx) / 3
y = (ay + by + cy) / 3

Program to illustrate the working of our solution,

Example

 Live Demo

#include <iostream>
using namespace std;
int main() {
   float tri[3][2] = {{-3, 1},{1.5, 0},{-3, -4}};
   cout<<"Centroid of triangle is (";
   cout<<((tri[0][0]+tri[1][0]+tri[2][0])/3)<<" , ";
   cout<<((tri[0][1]+tri[1][1]+tri[2][1])/3)<<")";
   return 0;
}

Output

Centroid of triangle is (-1.5 , -1)