Language: C++

#include <iostream>
using namespace std;

int main()
{
	int a,b,c;
	cin>>a>>b>>c;
	switch(a,b,c)
	{
		case a <= b && a <= c :
			switch(b,c)
				case b <= c:
					cout<<a<<" "<<b<<" "<<c<<endl;
				break;
				default:
					cout<<a<<" "<<c<<" "<<b<<endl;
		break;
		case b <= a && b >= c :
			switch(a,c)
				case a <= c:
					cout<<b<<" "<<a<<" "<<c<<endl;
				break;
				default:
					cout<<b<<" "<<c<<" "<<a<<endl;
		break;
		case c <= a && c <= b :
			switch(a,b)
				case a <= c:
					cout<<c<<" "<<a<<" "<<b<<endl;
				break;
				default:
					cout<<c<<" "<<b<<" "<<a<<endl;
	}
					
	return 0;
}
				
			
		
	


Compiler output:
a.cc: In function 'int main()':
a.cc:10:22: error: the value of 'a' is not usable in a constant expression
   10 |                 case a <= b && a <= c :
      |                      ^
a.cc:6:13: note: 'int a' is not const
    6 |         int a,b,c;
      |             ^
a.cc:10:22: error: the value of 'a' is not usable in a constant expression
   10 |                 case a <= b && a <= c :
      |                      ^
a.cc:6:13: note: 'int a' is not const
    6 |         int a,b,c;
      |             ^
a.cc:12:38: error: the value of 'b' is not usable in a constant expression
   12 |                                 case b <= c:
      |                                      ^
a.cc:6:15: note: 'int b' is not const
    6 |         int a,b,c;
      |               ^
a.cc:12:38: error: the value of 'b' is not usable in a constant expression
   12 |                                 case b <= c:
      |                                      ^
a.cc:6:15: note: 'int b' is not const
    6 |         int a,b,c;
      |               ^
a.cc:18:22: error: the value of 'b' is not usable in a constant expression
   18 |                 case b <= a && b >= c :
      |                      ^
a.cc:6:15: note: 'int b' is not const
    6 |         int a,b,c;
      |               ^
a.cc:18:22: error: the value of 'b' is not usable in a constant expression
   18 |                 case b <= a && b >= c :
      |                      ^
a.cc:6:15: note: 'int b' is not const
    6 |         int a,b,c;
      |               ^
a.cc:20:38: error: the value of 'a' is not usable in a constant expression
   20 |                                 case a <= c:
      |                                      ^
a.cc:6:13: note: 'int a' is not const
    6 |         int a,b,c;
      |             ^
a.cc:20:38: error: the value of 'a' is not usable in a constant expression
   20 |                                 case a <= c:
      |                                      ^
a.cc:6:13: note: 'int a' is not const
    6 |         int a,b,c;
      |             ^
a.cc:23:33: error: multiple default labels in one switch
   23 |                                 default:
      |                                 ^~~~~~~
a.cc:15:33: note: this is the first default label
   15 |                                 default:
      |                                 ^~~~~~~
a.cc:26:22: error: the value of 'c' is not usable in a constant expression
   26 |                 case c <= a && c <= b :
      |                      ^
a.cc:6:17: note: 'int c' is not const
    6 |         int a,b,c;
      |                 ^
a.cc:26:22: error: the value of 'c' is not usable in a constant expression
   26 |                 case c <= a && c <= b :
      |                      ^
a.cc:6:17: note: 'int c' is not const
    6 |         int a,b,c;
      |                 ^
a.cc:28:38: error: the value of 'a' is not usable in a constant expression
   28 |                                 case a <= c:
      |                                      ^
a.cc:6:13: note: 'int a' is not const
    6 |         int a,b,c;
      |             ^
a.cc:28:38: error: the value of 'a' is not usable in a constant expression
   28 |                                 case a <= c:
      |                                      ^
a.cc:6:13: note: 'int a' is not const
    6 |         int a,b,c;
      |             ^
a.cc:31:33: error: multiple default labels in one switch
   31 |                                 default:
      |                                 ^~~~~~~
a.cc:15:33: note: this is the first default label
   15 |                                 default:
      |                                 ^~~~~~~