Language: C++

using System;

class Program {
    static void Main() {
        char[] chars = { 'A', 'B', 'C', 'D', 'E' };

        while (true) {
            var maxNo = 0;
            var maxCount = 0;

            for (var i = 0; i < 5; i++) {
                var l = Console.ReadLine().Split(' ');
                var count = int.Parse(l[0]) + int.Parse(l[1]);

                if (count == 0)
                    return;

                if (count > maxCount) {
                    maxNo = i;
                    maxCount = count;
                }
            }

            Console.WriteLine(chars[maxNo] + " " + maxCount);
        }
    }
}

Compiler output:
a.cc:1:7: error: expected nested-name-specifier before 'System'
    1 | using System;
      |       ^~~~~~
a.cc:27:2: error: expected ';' after class definition
   27 | }
      |  ^
      |  ;
a.cc: In static member function 'static void Program::Main()':
a.cc:5:13: error: structured binding declaration cannot have type 'char'
    5 |         char[] chars = { 'A', 'B', 'C', 'D', 'E' };
      |             ^~
a.cc:5:13: note: type must be cv-qualified 'auto' or reference to cv-qualified 'auto'
a.cc:5:13: error: empty structured binding declaration
a.cc:5:16: error: expected initializer before 'chars'
    5 |         char[] chars = { 'A', 'B', 'C', 'D', 'E' };
      |                ^~~~~
a.cc:8:13: error: 'var' was not declared in this scope
    8 |             var maxNo = 0;
      |             ^~~
a.cc:9:17: error: expected ';' before 'maxCount'
    9 |             var maxCount = 0;
      |                 ^~~~~~~~
a.cc:11:22: error: expected ';' before 'i'
   11 |             for (var i = 0; i < 5; i++) {
      |                      ^
a.cc:11:29: error: 'i' was not declared in this scope
   11 |             for (var i = 0; i < 5; i++) {
      |                             ^
a.cc:12:21: error: expected ';' before 'l'
   12 |                 var l = Console.ReadLine().Split(' ');
      |                     ^
a.cc:13:21: error: expected ';' before 'count'
   13 |                 var count = int.Parse(l[0]) + int.Parse(l[1]);
      |                     ^~~~~
a.cc:15:21: error: 'count' was not declared in this scope
   15 |                 if (count == 0)
      |                     ^~~~~
a.cc:18:21: error: 'count' was not declared in this scope
   18 |                 if (count > maxCount) {
      |                     ^~~~~
a.cc:18:29: error: 'maxCount' was not declared in this scope
   18 |                 if (count > maxCount) {
      |                             ^~~~~~~~
a.cc:19:21: error: 'maxNo' was not declared in this scope
   19 |                     maxNo = i;
      |                     ^~~~~
a.cc:24:13: error: 'Console' was not declared in this scope
   24 |             Console.WriteLine(chars[maxNo] + " " + maxCount);
      |             ^~~~~~~
a.cc:24:31: error: 'chars' was not declared in this scope; did you mean 'char'?
   24 |             Console.WriteLine(chars[maxNo] + " " + maxCount);
      |                               ^~~~~
      |                               char
a.cc:24:37: error: 'maxNo' was not declared in this scope
   24 |             Console.WriteLine(chars[maxNo] + " " + maxCount);
      |                                     ^~~~~
a.cc:24:52: error: 'maxCount' was not declared in this scope
   24 |             Console.WriteLine(chars[maxNo] + " " + maxCount);
      |                                                    ^~~~~~~~