隐血红细胞:我写了一小段很笨的程序，希望高手指教

#include <iostream>
#include <string>
using namespace std;
int main();
{
double COURSE,COURSENUMBER;
char a=Intro to Computer Architecture;
b=Intro to Algorithms;
c=Software Engineering;
d=Operating System;
e=Programming Language Paradigms;

cout << "If you want to transform course number to course name, please input "
<< /" <<" 1 "<< /" << "." << /n
<< "If you want to transform course name to course number, please input "
<< /" <<" 2 "<< /" << "." << /n;
cin >> COURSE;
if (COURSE==1)
goto I;
if (COURSE==2)
goto II;
else endl;
I:
cout << "Please input the course number: ";
cin >> COURSENUMBER;
char COURSENAME(double COURSENUMBER);
{
switch (COURSENUMBER)
{
case 220:
return a;
case 230:
return b;
case 240:
return c;
case 270:
return d;
case 280:
return e;
default:
return endl;
}
}
cout << COURSENUMBER << /n << COURSENAME;
return 0;
II:
cout << "Please input the course name: ";
string COURSENAME;
cin >> COURSENAME;
double COURSENUMBER(char COURSENAME);
{
switch (COURSENAME)
{
case a:
return 220;
case b:
return 230;
case c:
return 240;
case d:
return 270;
case e:
return 280;
default:
return endl;
}
}
cout << COURSENAME << /n << COURSENUMBER;
return 0;

}