Language: C++

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

namespace AtCoderABC086
{
    class Program
    {
        public static void Main(string[] args)
        {
            string S = Console.ReadLine();
            string T = Console.ReadLine();
            bool flag = true;
            Dictionary<char, char> dict =  new Dictionary<char, char>();
            Dictionary<char, char> dict2 =  new Dictionary<char, char>();
            for (int i = 0; i < S.Length; i++)
            {
                if (dict.ContainsKey(S[i]) && dict[S[i]] != T[i])
                {
                    flag = false;
                    break;
                }
                if (dict2.ContainsKey(T[i]) && dict2[T[i]] != S[i])
                {
                    flag = false;
                    break;
                }
                if (!dict.ContainsKey(S[i])) dict[S[i]] = T[i];
                if (!dict2.ContainsKey(T[i])) dict2[T[i]] = S[i];
            }
            Console.WriteLine((flag)? "Yes": "No");
        }
    }
}


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.Linq;
      |       ^~~~~~
a.cc:3:7: error: expected nested-name-specifier before 'System'
    3 | using System.Collections;
      |       ^~~~~~
a.cc:4:7: error: expected nested-name-specifier before 'System'
    4 | using System.Collections.Generic;
      |       ^~~~~~
a.cc:10:15: error: expected ':' before 'static'
   10 |         public static void Main(string[] args)
      |               ^~~~~~~
      |               :
a.cc:10:33: error: 'string' has not been declared
   10 |         public static void Main(string[] args)
      |                                 ^~~~~~
a.cc:10:42: error: expected ',' or '...' before 'args'
   10 |         public static void Main(string[] args)
      |                                          ^~~~
a.cc:34:6: error: expected ';' after class definition
   34 |     }
      |      ^
      |      ;
a.cc: In static member function 'static void AtCoderABC086::Program::Main(int*)':
a.cc:12:13: error: 'string' was not declared in this scope
   12 |             string S = Console.ReadLine();
      |             ^~~~~~
a.cc:13:20: error: expected ';' before 'T'
   13 |             string T = Console.ReadLine();
      |                    ^
a.cc:15:13: error: 'Dictionary' was not declared in this scope
   15 |             Dictionary<char, char> dict =  new Dictionary<char, char>();
      |             ^~~~~~~~~~
a.cc:15:24: error: expected primary-expression before 'char'
   15 |             Dictionary<char, char> dict =  new Dictionary<char, char>();
      |                        ^~~~
a.cc:16:24: error: expected primary-expression before 'char'
   16 |             Dictionary<char, char> dict2 =  new Dictionary<char, char>();
      |                        ^~~~
a.cc:17:33: error: 'S' was not declared in this scope
   17 |             for (int i = 0; i < S.Length; i++)
      |                                 ^
a.cc:19:21: error: 'dict' was not declared in this scope
   19 |                 if (dict.ContainsKey(S[i]) && dict[S[i]] != T[i])
      |                     ^~~~
a.cc:19:61: error: 'T' was not declared in this scope
   19 |                 if (dict.ContainsKey(S[i]) && dict[S[i]] != T[i])
      |                                                             ^
a.cc:24:21: error: 'dict2' was not declared in this scope
   24 |                 if (dict2.ContainsKey(T[i]) && dict2[T[i]] != S[i])
      |                     ^~~~~
a.cc:24:39: error: 'T' was not declared in this scope
   24 |                 if (dict2.ContainsKey(T[i]) && dict2[T[i]] != S[i])
      |                                       ^
a.cc:29:22: error: 'dict' was not declared in this scope
   29 |                 if (!dict.ContainsKey(S[i])) dict[S[i]] = T[i];
      |                      ^~~~
a.cc:29:59: error: 'T' was not declared in this scope
   29 |                 if (!dict.ContainsKey(S[i])) dict[S[i]] = T[i];
      |                                                           ^
a.cc:30:22: error: 'dict2' was not declared in this scope
   30 |                 if (!dict2.ContainsKey(T[i])) dict2[T[i]] = S[i];
      |                      ^~~~~
a.cc:30:40: error: 'T' was not declared in this scope
   30 |                 if (!dict2.ContainsKey(T[i])) dict2[T[i]] = S[i];
      |                                        ^
a.cc:32:13: error: 'Console' was not declared in this scope
   32 |             Console.WriteLine((flag)? "Yes": "No");
      |             ^~~~~~~