Language: C++

#include <iostream>
using namesapce std;
int main(){
    int a,b,c;
    do{
    cin >> a >> b;
    c = a+b;
    if (c>1000000)
        cout << "7" << endl;
    else if (c>100000)
        cout << "6" << endl;
    else if (c>10000)
        cout << "5" << endl;
    else if (c>1000)
        cout << "4" << endl;
    else if (c>100)
        cout << "3" << endl;
    else if (c>10)
        cout << "2" << endl;
    else
        cout << "1" << endl;
} while (true);
}

Compiler output:
a.cc:2:7: error: expected nested-name-specifier before 'namesapce'
    2 | using namesapce std;
      |       ^~~~~~~~~
a.cc: In function 'int main()':
a.cc:6:5: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
    6 |     cin >> a >> b;
      |     ^~~
      |     std::cin
In file included from a.cc:1:
/usr/include/c++/14/iostream:62:18: note: 'std::cin' declared here
   62 |   extern istream cin;           ///< Linked to standard input
      |                  ^~~
a.cc:9:9: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
    9 |         cout << "7" << endl;
      |         ^~~~
      |         std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:9:24: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
    9 |         cout << "7" << endl;
      |                        ^~~~
      |                        std::endl
In file included from /usr/include/c++/14/iostream:41:
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
a.cc:11:9: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   11 |         cout << "6" << endl;
      |         ^~~~
      |         std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:11:24: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   11 |         cout << "6" << endl;
      |                        ^~~~
      |                        std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
a.cc:13:9: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   13 |         cout << "5" << endl;
      |         ^~~~
      |         std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:13:24: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   13 |         cout << "5" << endl;
      |                        ^~~~
      |                        std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
a.cc:15:9: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   15 |         cout << "4" << endl;
      |         ^~~~
      |         std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:15:24: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   15 |         cout << "4" << endl;
      |                        ^~~~
      |                        std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
a.cc:17:9: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   17 |         cout << "3" << endl;
      |         ^~~~
      |         std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:17:24: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   17 |         cout << "3" << endl;
      |                        ^~~~
      |                        std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
a.cc:19:9: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   19 |         cout << "2" << endl;
      |         ^~~~
      |         std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:19:24: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   19 |         cout << "2" << endl;
      |                        ^~~~
      |                        std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
a.cc:21:9: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   21 |         cout << "1" << endl;
      |         ^~~~
      |         std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:21:24: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   21 |         cout << "1" << endl;
      |                        ^~~~
      |                        std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~