foo.cc: In function 'void Hanoia(int, char, char, char, int, int, int)':
foo.cc:18:9: error: return-statement with a value, in function returning 'void' [-fpermissive]
  return a;
         ^
foo.cc: In function 'void Hanoib(int, char, char, char, int, int, int)':
foo.cc:34:9: error: return-statement with a value, in function returning 'void' [-fpermissive]
  return b;
         ^
foo.cc: In function 'void Hanoic(int, char, char, char, int, int, int)':
foo.cc:50:9: error: return-statement with a value, in function returning 'void' [-fpermissive]
  return c;
         ^
foo.cc: In function 'int main()':
foo.cc:63:6: error: redeclaration of 'int a'
  int a=Hanoia(n, A,B,C,a,b,c);
      ^
foo.cc:56:6: note: 'int a' previously declared here
  int a,b=0,c=0;
      ^
foo.cc:64:6: error: redeclaration of 'int b'
  int b=Hanoib(n, A,B,C,a,b,c);
      ^
foo.cc:56:8: note: 'int b' previously declared here
  int a,b=0,c=0;
        ^
foo.cc:65:6: error: redeclaration of 'int c'
  int c=Hanoic(n, A,B,C,a,b,c);
      ^
foo.cc:56:12: note: 'int c' previously declared here
  int a,b=0,c=0;
            ^

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