foo.cc:31:39: error: ISO C++ forbids declaration of 'setinter' with no type [-fpermissive]
 setinter(int a[],int na,int b[],int nb)
                                       ^
foo.cc: In function 'int setinter(int*, int, int*, int)':
foo.cc:31:1: error: ambiguating new declaration of 'int setinter(int*, int, int*, int)'
 setinter(int a[],int na,int b[],int nb)
 ^~~~~~~~
foo.cc:4:6: note: old declaration 'void setinter(int*, int, int*, int)'
 void setinter(int a[],int na,int b[],int nb);
      ^~~~~~~~
foo.cc:33:6: warning: unused variable 'l' [-Wunused-variable]
  int l=0; 
      ^
foo.cc:47:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
foo.cc: At global scope:
foo.cc:48:27: error: ISO C++ forbids declaration of 'Serch' with no type [-fpermissive]
 Serch(int a[],int n, int x)
                           ^

自豪的采用HydroJudge(https://github.com/hydro-dev/Hydro)进行评测。