/in/foo.cc: In function 'int main()':
/in/foo.cc:37:44: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   37 |             (num[i] == num[j]) && (ans = i + j >> 1);
      |                                          ~~^~~
/in/foo.cc:29:15: warning: unused variable 'z' [-Wunused-variable]
   29 |     int i, j, z, now, next;
      |               ^
/in/foo.cc:29:18: warning: unused variable 'now' [-Wunused-variable]
   29 |     int i, j, z, now, next;
      |                  ^~~
/in/foo.cc:29:23: warning: unused variable 'next' [-Wunused-variable]
   29 |     int i, j, z, now, next;
      |                       ^~~~