foo.cc: In function 'void fun(int, int)':
foo.cc:6:17: warning: unused variable 'j' [-Wunused-variable]
    6 |         int i,q,j=0;
      |                 ^
foo.cc: In function 'int main()':
foo.cc:16:15: warning: unused variable 'i' [-Wunused-variable]
   16 |         int n,i,j;
      |               ^
foo.cc:16:17: warning: unused variable 'j' [-Wunused-variable]
   16 |         int n,i,j;
      |                 ^

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