foo.cc: In function 'int main()':
foo.cc:3:26: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
    3 | #define rep(i,n) for(int (i)=1;(i)<=n;++(i))
      |                          ^~~
foo.cc:16:9: note: in expansion of macro 'rep'
   16 |         rep(i,n)a[i]=read();
      |         ^~~
foo.cc:3:26: note: remove parentheses
    3 | #define rep(i,n) for(int (i)=1;(i)<=n;++(i))
      |                          ^~~
foo.cc:16:9: note: in expansion of macro 'rep'
   16 |         rep(i,n)a[i]=read();
      |         ^~~

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