Language: C++

using System;

class Program
{
    static bool checking(int[] a)
    {
        return (a[0] + a[1] == a[2] || a[1] + a[2] == a[0] || a[2] + a[0] == a[1]);
    }

    static int Main()
    {   
        int[] a = new int[3];
        int inp,n;
        string[] str;
        string result;

        n = int.Parse(Console.ReadLine());
        for (int i = 0; i < n; i++)
        {
            str = (Console.ReadLine()).Split(' ');
            for (int j = 0; j < 3; j++)
            {
                
                inp = int.Parse(str[j]);
                a[j] = inp * inp;
            }

            if (checking(a))
                result = "YES";
            else
                result = "NO";

            Console.WriteLine("{0}", result);

        }

        



        return 0;
    }
}
       

Compiler output:
a.cc:1:7: error: expected nested-name-specifier before 'System'
    1 | using System;
      |       ^~~~~~
a.cc:5:32: error: expected ',' or '...' before 'a'
    5 |     static bool checking(int[] a)
      |                                ^
a.cc:43:2: error: expected ';' after class definition
   43 | }
      |  ^
      |  ;
a.cc: In static member function 'static bool Program::checking(int*)':
a.cc:7:17: error: 'a' was not declared in this scope
    7 |         return (a[0] + a[1] == a[2] || a[1] + a[2] == a[0] || a[2] + a[0] == a[1]);
      |                 ^
a.cc: In static member function 'static int Program::Main()':
a.cc:12:12: error: structured binding declaration cannot have type 'int'
   12 |         int[] a = new int[3];
      |            ^~
a.cc:12:12: note: type must be cv-qualified 'auto' or reference to cv-qualified 'auto'
a.cc:12:12: error: empty structured binding declaration
a.cc:12:15: error: expected initializer before 'a'
   12 |         int[] a = new int[3];
      |               ^
a.cc:14:9: error: 'string' was not declared in this scope
   14 |         string[] str;
      |         ^~~~~~
a.cc:14:16: error: expected primary-expression before ']' token
   14 |         string[] str;
      |                ^
a.cc:15:16: error: expected ';' before 'result'
   15 |         string result;
      |                ^~~~~~
a.cc:17:13: error: expected primary-expression before 'int'
   17 |         n = int.Parse(Console.ReadLine());
      |             ^~~
a.cc:20:13: error: 'str' was not declared in this scope; did you mean 'std'?
   20 |             str = (Console.ReadLine()).Split(' ');
      |             ^~~
      |             std
a.cc:20:20: error: 'Console' was not declared in this scope
   20 |             str = (Console.ReadLine()).Split(' ');
      |                    ^~~~~~~
a.cc:24:23: error: expected primary-expression before 'int'
   24 |                 inp = int.Parse(str[j]);
      |                       ^~~
a.cc:25:17: error: 'a' was not declared in this scope
   25 |                 a[j] = inp * inp;
      |                 ^
a.cc:28:26: error: 'a' was not declared in this scope
   28 |             if (checking(a))
      |                          ^
a.cc:29:17: error: 'result' was not declared in this scope
   29 |                 result = "YES";
      |                 ^~~~~~
a.cc:31:17: error: 'result' was not declared in this scope
   31 |                 result = "NO";
      |                 ^~~~~~
a.cc:33:38: error: 'result' was not declared in this scope
   33 |             Console.WriteLine("{0}", result);
      |                                      ^~~~~~