foo.cc:3:36: error: ISO C++ forbids declaration of 'zhebancz' with no type [-fpermissive]
    3 | zhebancz(int *a,int l,int r,int key)
      |                                    ^
foo.cc: In function 'int zhebancz(int*, int, int, int)':
foo.cc:28:1: warning: no return statement in function returning non-void [-Wreturn-type]
   28 | }
      | ^

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