foo.cc: In member function 'void tree::build(int, int, int)':
foo.cc:56:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   56 |         int mid = L + R >> 1;
      |                   ~~^~~
foo.cc: In member function 'void tree::modify(int, int, int, int)':
foo.cc:66:27: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   66 |         int mid = nd[p].L + nd[p].R >> 1;
      |                   ~~~~~~~~^~~~~~~~~
foo.cc: In member function 'void tree::query(int, int, Numbr*)':
foo.cc:80:27: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   80 |         int mid = nd[p].L + nd[p].R >> 1;
      |                   ~~~~~~~~^~~~~~~~~
foo.cc: In member function 'void tree::changeTree(int, int, Numbr*, int)':
foo.cc:94:27: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   94 |         int mid = nd[p].L + nd[p].R >> 1;
      |                   ~~~~~~~~^~~~~~~~~
foo.cc: In function 'ull gcd(ull, ull)':
foo.cc:21:12: warning: control reaches end of non-void function [-Wreturn-type]
   21 |         gcd(b, a % b);
      |         ~~~^~~~~~~~~~

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