foo.cc: In function 'int main()':
foo.cc:12:7: warning: unnecessary parentheses in declaration of 'n' [-Wparentheses]
   12 |   char(n)='X';
      |       ^
foo.cc:12:8: warning: unused variable 'n' [-Wunused-variable]
   12 |   char(n)='X';
      |        ^
foo.cc:15:7: warning: unnecessary parentheses in declaration of 'n' [-Wparentheses]
   15 |   char(n)=n;
      |       ^

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