# Maximum area of quadrilateral in C++

## Problem statement

Given four sides of quadrilateral a, b, c, d, find the maximum area of the quadrilateral possible from the given sides.

## Algorithm

We can use below Brahmagupta’s formula to solve this problem −

√(s-a)(s-b)(s-c)(s-d)

In above formula s is semi-perimeter. It is calculated as follows −

S = (a + b + c + d) / 2

## Example

Let us now see an example −

Live Demo

#include <bits/stdc++.h>
using namespace std;
double getMaxArea(double a, double b, double c, double d) {
double s = (a + b + c + d) / 2;
double area = (s - a) * (s - b) * (s - c) * (s - d);
return sqrt(area);
}
int main() {
double a = 1, b = 2.5, c = 1.8, d = 2;
cout << "Maximum area = " << getMaxArea(a, b, c, d) << endl;
return 0;
}

## Output

Maximum area = 3.05