The program is getting an infinite loop only if I enter a letter or any character that isn't an integer.
cout<<"\n *GEOMETRY CALCULATOR*\n"
<<"\nto stop Anytime ENTER -1\n"
<<endl;
cout<<"please choose"
<<"\n1-6 choices given below:\n"<<endl
<<"1:Circle\n"
<<"2:Rectangle\n"
<<"3:Triangle\n"
<<"4:Parallellogram\n"
<<"5:Trapezoid\n"
<<"6:square\n"
<<endl;
//welcome to the GEOMETRY CALCULATOR.
int choice;
const float PI = 3.14159 ;
float area , circumference , diameter , perimeter , radius;
cout<<"choose shape to calculate...\n";
cin>>choice;
while(choice != -1)
{
if(!(choice>=1 && choice<=6))
cout<<"\nplease enter only 1-6\n"
<<"------------------------\n"<<endl;
//if the choice is not in the given choices
