Switch statement example in c++ to calculate grade points gpa

C++ Program

#include<iostream>
using namespace std;
int main() {
	char grade;
	double gpa=0.0;
	cout<<"Enter your Grade=  ";
	cin>>grade;
	switch(grade) {
		case'A':
		  case'a':
		  gpa=4.0;
		cout<<"your GPA is "<<gpa;
		break;
		case'B':
		    case'b':
		    gpa=3.0;
		cout<<"your GPA is "<<gpa;
		break;
		case'C':
		     case'c':
		     gpa=2.0;
		cout<<"your GPA is "<<gpa;
		break;
		case'D':
		      case'd':
		      gpa=1.0;
		cout<<"your GPA is "<<gpa;
		break;
		case'F':
		       case'f':
		       gpa=0.0;
		cout<<"your GPA is "<<gpa;
		break;
		default:
		    cout<<"invalid grade entered";
		break;
	}
	return 0;
}