Missing side of rectangular triangle

//This program asks you to enter the value of each side of triangle, then sends answer. It tells you the the value of missing side of rectangular triangle. 
#include <iostream>
#include <cmath>
using namespace std;

int main()
{
    
    double FirstCathetusOfTriangle;
    double SecondCathetusOfTriangle;
    double HypotenuseOfTriangle;


    cout << "Enter first cathetus of triangle, if unknown enter 0" << endl;
    cin >> FirstCathetusOfTriangle;
    cout << "Enter second cathetus of triangle, if unknown enter 0"<< endl;
    cin >> SecondCathetusOfTriangle;
    cout << "Enter hypotenuse of triangle, if unknown enter 0" << endl;
    cin >> HypotenuseOfTriangle;


    
    if(FirstCathetusOfTriangle == 0)
    {
        cout << "\n";    
        cout << sqrt(pow(HypotenuseOfTriangle,2)-pow(SecondCathetusOfTriangle,2));
    }
    else if (SecondCathetusOfTriangle == 0)
    {
        cout << "\n";    
        cout << sqrt(pow(HypotenuseOfTriangle,2)-pow(FirstCathetusOfTriangle,2));
    }
    else
    {
        cout << "\n";
        cout << sqrt(pow(FirstCathetusOfTriangle,2)+pow(SecondCathetusOfTriangle,2));
    }

 return 0;   
}