Area of triangle in c++

#include<iostream>
#include<conio.h>
using namespace std;
int main()
{
        int base, height;
        float area;
        cout<<"Enter base and height\n";
        cin>>base>>height;
        area=0.5*base*height;
        cout<<"Area of triangle : "<<area;
        getch();
        return 0;
}

Output

Area of rectangle in c++

#include<iostream>
#include<conio.h>
using namespace std;
int main()
{
        float lenght, breath;
        double area;
        cout<<"Enter length and breath\n";
        cin>>lenght>>breath;
        area=lenght*breath;
        cout<<"Area of rectangle : "<<area;
        getch();
        return 0;
}

Output

Area of circle in c++

#include<iostream>
#include<conio.h>
using namespace std;
int main()
{
        float radius;
        double area;
        cout<<"Enter radius of circle : ";
        cin>>radius;
        area=3.14*radius*radius;
        cout<<"Area of circle : "<<area;
        getch();
        return 0;
}

Output