./GD-Senior/answers/GD-S*****/lock/lock.cpp:9:19: error: ‘int brk’ redeclared as different kind of entity
    9 | int n,m,ans=0,x,y,brk;
      |                   ^~~
In file included from /usr/include/x86_64-linux-gnu/bits/sigstksz.h:24,
                 from /usr/include/signal.h:328,
                 from /usr/include/c++/11/csignal:42,
                 from /usr/include/x86_64-linux-gnu/c++/11/bits/stdc++.h:43,
                 from ./GD-Senior/answers/GD-S*****/lock/lock.cpp:1:
/usr/include/unistd.h:1070:12: note: previous declaration ‘int brk(void*)’
 1070 | extern int brk (void *__addr) __THROW __wur;
      |            ^~~

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