运行 ID: 110223

Main.cc:10:22: error: ISO C++ forbids declaration of ‘quicksort’ with no type [-fpermissive]
 quicksort(int l,int r)
                      ^
Main.cc: In function ‘int quicksort(int, int)’:
Main.cc:21:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^