Language: C++

using System;
using System.Collections.Generic;
using System.Linq;
using System.Diagnostics;

class Program
{
    static void Main(string[] args)
    {
        var sc = new Scanner();
        int a = sc.nextInt();
        int b = sc.nextInt();


        if (a >= 13) Console.WriteLine(b);
        else if (a >= 6) Console.WriteLine(b / 2);
        else Console.WriteLine(0);
    }
}

// chokudai's Scanner
class Scanner
{
    string[] s;
    int i;

    char[] cs = new char[] { ' ' };

    public Scanner()
    {
        s = new string[0];
        i = 0;
    }

    public string next()
    {
        if (i < s.Length) return s[i++];
        string st = Console.ReadLine();
        while (st == "") st = Console.ReadLine();
        s = st.Split(cs, StringSplitOptions.RemoveEmptyEntries);
        if (s.Length == 0) return next();
        i = 0;
        return s[i++];
    }

    public int nextInt()
    {
        return int.Parse(next());
    }

    public int[] ArrayInt(int N, int add = 0)
    {
        int[] Array = new int[N];
        for (int i = 0; i < N; i++)
        {
            Array[i] = nextInt() + add;
        }
        return Array;
    }

    public long nextLong()
    {
        return long.Parse(next());
    }

    public long[] ArrayLong(int N, long add = 0)
    {
        long[] Array = new long[N];
        for (int i = 0; i < N; i++)
        {
            Array[i] = nextLong() + add;
        }
        return Array;
    }

    public double nextDouble()
    {
        return double.Parse(next());
    }

    public double[] ArrayDouble(int N, double add = 0)
    {
        double[] Array = new double[N];
        for (int i = 0; i < N; i++)
        {
            Array[i] = nextDouble() + add;
        }
        return Array;
    }
}


Compiler output:
a.cc:1:7: error: expected nested-name-specifier before 'System'
    1 | using System;
      |       ^~~~~~
a.cc:2:7: error: expected nested-name-specifier before 'System'
    2 | using System.Collections.Generic;
      |       ^~~~~~
a.cc:3:7: error: expected nested-name-specifier before 'System'
    3 | using System.Linq;
      |       ^~~~~~
a.cc:4:7: error: expected nested-name-specifier before 'System'
    4 | using System.Diagnostics;
      |       ^~~~~~
a.cc:8:22: error: 'string' has not been declared
    8 |     static void Main(string[] args)
      |                      ^~~~~~
a.cc:8:31: error: expected ',' or '...' before 'args'
    8 |     static void Main(string[] args)
      |                               ^~~~
a.cc:19:2: error: expected ';' after class definition
   19 | }
      |  ^
      |  ;
a.cc: In static member function 'static void Program::Main(int*)':
a.cc:10:9: error: 'var' was not declared in this scope
   10 |         var sc = new Scanner();
      |         ^~~
a.cc:11:17: error: 'sc' was not declared in this scope
   11 |         int a = sc.nextInt();
      |                 ^~
a.cc:15:22: error: 'Console' was not declared in this scope
   15 |         if (a >= 13) Console.WriteLine(b);
      |                      ^~~~~~~
a.cc:16:26: error: 'Console' was not declared in this scope
   16 |         else if (a >= 6) Console.WriteLine(b / 2);
      |                          ^~~~~~~
a.cc:17:14: error: 'Console' was not declared in this scope
   17 |         else Console.WriteLine(0);
      |              ^~~~~~~
a.cc: At global scope:
a.cc:24:5: error: 'string' does not name a type
   24 |     string[] s;
      |     ^~~~~~
a.cc:27:9: error: expected unqualified-id before '[' token
   27 |     char[] cs = new char[] { ' ' };
      |         ^
a.cc:29:11: error: expected ':' before 'Scanner'
   29 |     public Scanner()
      |           ^~~~~~~~
      |           :
a.cc:35:11: error: expected ':' before 'string'
   35 |     public string next()
      |           ^~~~~~~
      |           :
a.cc:35:12: error: 'string' does not name a type
   35 |     public string next()
      |            ^~~~~~
a.cc:46:11: error: expected ':' before 'int'
   46 |     public int nextInt()
      |           ^~~~
      |           :
a.cc:51:11: error: expected ':' before 'int'
   51 |     public int[] ArrayInt(int N, int add = 0)
      |           ^~~~
      |           :
a.cc:51:15: error: expected unqualified-id before '[' token
   51 |     public int[] ArrayInt(int N, int add = 0)
      |               ^
a.cc:61:11: error: expected ':' before 'long'
   61 |     public long nextLong()
      |           ^~~~~
      |           :
a.cc:66:11: error: expected ':' before 'long'
   66 |     public long[] ArrayLong(int N, long add = 0)
      |           ^~~~~
      |           :
a.cc:66:16: error: expected unqualified-id before '[' token
   66 |     public long[] ArrayLong(int N, long add = 0)
      |                ^
a.cc:76:11: error: expected ':' before 'double'
   76 |     public double nextDouble()
      |           ^~~~~~~
      |           :
a.cc:81:11: error: expected ':' before 'double'
   81 |     public double[] ArrayDouble(int N, double add = 0)
      |           ^~~~~~~
      |           :
a.cc:81:18: error: expected unqualified-id before '[' token
   81 |     public double[] ArrayDouble(int N, double add = 0)
      |                  ^
a.cc:90:2: error: expected ';' after class definition
   90 | }
      |  ^
      |  ;
a.cc: In constructor 'Scanner::Scanner()':
a.cc:31:9: error: 's' was not declared in this scope
   31 |         s = new string[0];
      |         ^
a.cc:31:17: error: 'string' does not name a type
   31 |         s = new string[0];
      |                 ^~~~~~
a.cc: In member function 'int Scanner::nextInt()':
a.cc:48:16: error: expected primary-expression before 'int'
   48 |         return int.Parse(next());
      |                ^~~
a.cc:48:16: error: expected ';' before 'int'
a.cc:48:19: error: expected unqualified-id before '.' token
   48 |         return int.Parse(next());
      |                   ^
a.cc: In member function 'long int Scanner::nextLong()':
a.cc:63:16: error: expected primary-expression before 'long'
   63 |         return long.Parse(next());
      |                ^~~~
a.cc:63:16: error: expected ';' before 'long'
a.cc:63:20: error: expected unqualified-id before '.' token
   63 |         return long.Parse(next());
      |                    ^
a.cc: In member function 'double Scanner::nextDouble()':
a.cc:78:16: error: expected primary-expression before 'double'
   78 |         return double.Parse(next());
      |                ^~~~~~
a.cc:78:16: error: expected ';' before 'double'
a.cc:78:22: error: expected unqualified-id before '.' token
   78 |         return double.Parse(next());
      |                      ^