c++ loop its not end the program wont end : can u tell whats the mistake t runs ok but program wont end i a m new to programming please i need help i have posted the code any one v=can check and help me please and am using dev c++ for this and i dont know why its doing like this uuuuurgghhhhhh

    #include <iostream>
    using namespace std;

    main(){
 	
	char num;
	again:
		

     int usr;
     float area;

    cout <<"\nEnter 1 to calculate area of rectangle\n";
    cout <<"Enter 2 to calculate area of trapezoid\n";
    cout <<"\nEnter your choice: ";
    cin >> usr;
    if(usr==1)

     {	
    double width, length;
    cout <<"Enter the width of rectangle: ";
    cin >> width;
    cout <<"Enter the length of rectangle: ";
    cin >> length;
    area=length*width;
    cout <<"The area of rectangle is: "<< area;
    }


    if (usr==2)
    {	
    double base1, base2, height;
    cout <<"Enter the base 1 of trapezoid: ";
    cin >> base1;
    cout <<"Enter the base 2 of trapezoid: ";
    cin >> base2;
    cout <<"Enter the height of trapezoid: ";
    cin >> height;
    area= (((base1 + base2) /2)*height);
    cout <<"The area of trapezoid is: "<< area;
    }
    cout <<"\n\ndo you want to do another calculation?";
    cin >> num;{
    goto again;
    }
    if (num=='y')

    {
    goto again;
    }
    if(num=='n'){
    exit (0);}
     }