foo.cc: In function 'int main()':
foo.cc:16:25: warning: init-statement in selection statements only available with '-std=c++17' or '-std=gnu++17' [-Wc++17-extensions]
   16 |                 else if(X==2001&&Y==10&&Z==4）
      |                         ^
foo.cc:16:44: error: unable to find numeric literal operator 'operator""\U0000ff09'
   16 |                 else if(X==2001&&Y==10&&Z==4）
      |                                            ^~~
foo.cc:16:44: note: use '-fext-numeric-literals' to enable more built-in suffixes
foo.cc:18:17: error: expected primary-expression before 'else'
   18 |                 else
      |                 ^~~~
foo.cc:17:43: error: expected ')' before 'else'
   17 |                         cout<<"YES"<<endl;
      |                                           ^
      |                                           )
   18 |                 else
      |                 ~~~~                       
foo.cc:16:24: note: to match this '('
   16 |                 else if(X==2001&&Y==10&&Z==4）
      |                        ^
foo.cc:6:14: warning: unused variable 'YES' [-Wunused-variable]
    6 |         char YES,NO;
      |              ^~~
foo.cc:6:18: warning: unused variable 'NO' [-Wunused-variable]
    6 |         char YES,NO;
      |                  ^~
foo.cc: At global scope:
foo.cc:22:9: error: expected unqualified-id before 'return'
   22 |         return 0;
      |         ^~~~~~
foo.cc:23:1: error: expected declaration before '}' token
   23 | }
      | ^

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