/in/foo.cc:16:4: error: 'maxn' was not declared in this scope
 }e[maxn];
    ^~~~
/in/foo.cc: In function 'void read(int&)':
/in/foo.cc:24:20: error: 'ch' was not declared in this scope
   x=(x<<1)+(x<<3)+(ch^48);
                    ^~
/in/foo.cc: In function 'bool judge(db)':
/in/foo.cc:36:14: error: 'e' was not declared in this scope
         now+=e[i].dis/v;
              ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:45:14: error: 'e' was not declared in this scope
         read(e[i].s);
              ^