foo.cc:9: warning: ignoring '#pragma comment ' [-Wunknown-pragmas]
    9 | #pragma comment(linker,"/STACK:1024000000,1024000000")
      | 
foo.cc: In function 'int main()':
foo.cc:55:9: warning: unused variable 'x' [-Wunused-variable]
   55 |     int x,y,z;
      |         ^
foo.cc:55:11: warning: unused variable 'y' [-Wunused-variable]
   55 |     int x,y,z;
      |           ^
foo.cc:55:13: warning: unused variable 'z' [-Wunused-variable]
   55 |     int x,y,z;
      |             ^

[Hydro](https://hydro.ac)提供评测服务