Calculate Area&Perimeter

#include <iostream>
#include <string>
#include <cmath>

using namespace std;

void calculateTriangle()
{
    double sideA, sideB, sideC, halfP;

    cout << "Calculate perimeter and area of TRIANGLE" << endl;
    cout << "" << endl;

    do
    {
        cout << "Enter value of side A(base) in cm: ";
        cin >> sideA;

    } while (sideA <= 0);

    cout << "" << endl;

    do
    {
        cout << "Enter value of side B(left hit) in cm: ";
        cin >> sideB;

    } while (sideB <= 0);

    cout << "" << endl;

    do
    {
        cout << "Enter value of side C(right hit) in cm: ";
        cin >> sideC;

    } while (sideC <= 0);

    cout << "" << endl;

    halfP = (sideA + sideB + sideC) / 2;

    cout << "Perimeter is: " << sideA + sideB + sideC << " cm" << endl;
    cout << "Area is: " << sqrt(halfP * (halfP - sideA) * (halfP - sideB) * (halfP - sideC)) << " cm2" << endl;
}

void calculateTrapezoid()
{
    double sideA, sideB, sideC, sideD, heigth;

    cout << "Calculate perimeter and area of TRAPEZOID" << endl;
    cout << "" << endl;

    do
    {
        cout << "Enter value of side A(big base) in cm: ";
        cin >> sideA;

    } while (sideA <= 0);

    cout << "" << endl;

    do
    {
        cout << "Enter value of side B(small base) in cm: ";
        cin >> sideB;

    } while (sideB <= 0);

    cout << "" << endl;

    do
    {
        cout << "Enter value of side C(left hit) in cm: ";
        cin >> sideC;

    } while (sideC <= 0);

    cout << "" << endl;

    do
    {
        cout << "Enter value of side D(right hit) in cm: ";
        cin >> sideD;

    } while (sideD <= 0);

    cout << "" << endl;

    do
    {
        cout << "Enter value of heigth in cm: ";
        cin >> heigth;

    } while (heigth <= 0);

    cout << "" << endl;

    cout << "" << endl;
    cout << "Perimeter is: " << sideA + sideB + sideC + sideD << " cm" << endl;
    cout << "Area is: " << ((sideA + sideB) * heigth) / 2 << " cm2" << endl;
}

int main()
{
    string strChoose;
    unsigned int choose;

    do
    {
        cout << "Enter value of figure\n[1]Triangle\n[2]Trapezoid\n: ";
        cin >> choose;
        cout << "" << endl;

        switch (choose)
        {
        case 1:
            calculateTriangle();
            break;
        case 2:
            calculateTrapezoid();
            break;
        default:
            break;
        }


        if (choose >= 1 && choose <= 2) {

            cout << "" << endl;
            do
            {
                cout << "New calculation? [y/Y - Yes or n/N - No]: ";
                cin >> strChoose;

                if (strChoose == "Y" || strChoose == "y" || strChoose == "N" || strChoose == "n") {
                    break;
                }
                else {
                    strChoose = "countine";
                    continue;
                }

            } while (true);


            if (strChoose == "Y" || strChoose == "y") {
                system("CLS");
                choose = 0;
            }
            else {
                exit(0);
            }

        }
        else {
            choose = 0;
        }


    } while (choose < 1 || choose > 2);

    return 0;
}