Language: C++

using System;
class Program
 {
        static void Main(string[] args)
        {
    　　int a,b,c;
            a = int.Parse(Console.ReadLine()); //標準入力
            string[] str = Console.ReadLine().Split(' ');//2つ以上のスペース区切り入力の取得
            b = int.Parse(str[0]);  //数値で受け取りたい場合は変換する
            c = int.Parse(str[1]);
　　　d = int.Parse(str[2]);
  e = int.Parse(str[3]);
int f=0;
if(b*c>d*e)
f = b*c;
else
f = d*e;
　　　　　　　Console.WriteLine(f);//改行付き出力
            
        }
 }

Compiler output:
a.cc:6:5: error: extended character 　 is not valid in an identifier
    6 |     　　int a,b,c;
      |     ^
a.cc:6:5: error: extended character 　 is not valid in an identifier
a.cc:11:1: error: extended character 　 is not valid in an identifier
   11 | 　　　d = int.Parse(str[2]);
      | ^
a.cc:11:1: error: extended character 　 is not valid in an identifier
a.cc:11:1: error: extended character 　 is not valid in an identifier
a.cc:18:1: error: extended character 　 is not valid in an identifier
   18 | 　　　　　　　Console.WriteLine(f);//改行付き出力
      | ^
a.cc:18:1: error: extended character 　 is not valid in an identifier
a.cc:18:1: error: extended character 　 is not valid in an identifier
a.cc:18:1: error: extended character 　 is not valid in an identifier
a.cc:18:1: error: extended character 　 is not valid in an identifier
a.cc:18:1: error: extended character 　 is not valid in an identifier
a.cc:18:1: error: extended character 　 is not valid in an identifier
a.cc:1:7: error: expected nested-name-specifier before 'System'
    1 | using System;
      |       ^~~~~~
a.cc:4:26: error: 'string' has not been declared
    4 |         static void Main(string[] args)
      |                          ^~~~~~
a.cc:4:35: error: expected ',' or '...' before 'args'
    4 |         static void Main(string[] args)
      |                                   ^~~~
a.cc:21:3: error: expected ';' after class definition
   21 |  }
      |   ^
      |   ;
a.cc: In static member function 'static void Program::Main(int*)':
a.cc:6:5: error: '\U00003000\U00003000int' was not declared in this scope
    6 |     　　int a,b,c;
      |     ^~~~~~~
a.cc:7:13: error: 'a' was not declared in this scope
    7 |             a = int.Parse(Console.ReadLine()); //標準入力
      |             ^
a.cc:7:17: error: expected primary-expression before 'int'
    7 |             a = int.Parse(Console.ReadLine()); //標準入力
      |                 ^~~
a.cc:8:13: error: 'string' was not declared in this scope
    8 |             string[] str = Console.ReadLine().Split(' ');//2つ以上のスペース区切り入力の取得
      |             ^~~~~~
a.cc:8:20: error: expected primary-expression before ']' token
    8 |             string[] str = Console.ReadLine().Split(' ');//2つ以上のスペース区切り入力の取得
      |                    ^
a.cc:9:13: error: 'b' was not declared in this scope
    9 |             b = int.Parse(str[0]);  //数値で受け取りたい場合は変換する
      |             ^
a.cc:9:17: error: expected primary-expression before 'int'
    9 |             b = int.Parse(str[0]);  //数値で受け取りたい場合は変換する
      |                 ^~~
a.cc:10:13: error: 'c' was not declared in this scope
   10 |             c = int.Parse(str[1]);
      |             ^
a.cc:10:17: error: expected primary-expression before 'int'
   10 |             c = int.Parse(str[1]);
      |                 ^~~
a.cc:11:1: error: '\U00003000\U00003000\U00003000d' was not declared in this scope
   11 | 　　　d = int.Parse(str[2]);
      | ^~~~~~~
a.cc:11:11: error: expected primary-expression before 'int'
   11 | 　　　d = int.Parse(str[2]);
      |           ^~~
a.cc:12:3: error: 'e' was not declared in this scope
   12 |   e = int.Parse(str[3]);
      |   ^
a.cc:12:7: error: expected primary-expression before 'int'
   12 |   e = int.Parse(str[3]);
      |       ^~~
a.cc:14:8: error: 'd' was not declared in this scope
   14 | if(b*c>d*e)
      |        ^
a.cc:18:1: error: '\U00003000\U00003000\U00003000\U00003000\U00003000\U00003000\U00003000Console' was not declared in this scope
   18 | 　　　　　　　Console.WriteLine(f);//改行付き出力
      | ^~~~~~~~~~~~~~~~~~~~~