/in/foo.cc: In function 'int main()':
/in/foo.cc:13:20: warning: unused variable 'maxn' [-Wunused-variable]
 long n,i,j,x,y,l,k,maxn;
                    ^~~~
/in/foo.cc: At global scope:
/in/foo.cc:38:1: error: 'maxn' does not name a type
 maxn=f[k];
 ^~~~
/in/foo.cc:39:1: error: 'cout' does not name a type
 cout<<k;//先输出起始点
 ^~~~
/in/foo.cc:40:1: error: 'k' does not name a type
 k=suf[k];
 ^
/in/foo.cc:41:1: error: expected unqualified-id before 'while'
 while(k!=0)//向后的链表
 ^~~~~
/in/foo.cc:46:1: error: 'cout' does not name a type
 cout<<endl;
 ^~~~
/in/foo.cc:47:1: error: 'cout' does not name a type
 cout<<maxn<<endl;
 ^~~~
/in/foo.cc:48:1: error: expected unqualified-id before 'return'
 return 0;
 ^~~~~~
/in/foo.cc:49:1: error: expected declaration before '}' token
 }
 ^