/in/foo.cc:18:23: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   18 | const int N = 1 << 30 - 1;
      |                    ~~~^~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:33:12: warning: unused variable 'j' [-Wunused-variable]
   33 |     int i, j, x, y, z;
      |            ^
/in/foo.cc:33:15: warning: unused variable 'x' [-Wunused-variable]
   33 |     int i, j, x, y, z;
      |               ^
/in/foo.cc:33:18: warning: unused variable 'y' [-Wunused-variable]
   33 |     int i, j, x, y, z;
      |                  ^