foo.cc: In function 'void Work()':
foo.cc:58:13: error: 'read' was not declared in this scope
o_pos = read() ^ last_ans, K = read() ^ last_ans;
^~~~
foo.cc:58:13: note: suggested alternative: 'head'
o_pos = read() ^ last_ans, K = read() ^ last_ans;
^~~~
head
foo.cc: In function 'int main()':
foo.cc:76:9: error: 'read' was not declared in this scope
N = read();
^~~~
foo.cc:76:9: note: suggested alternative: 'head'
N = read();
^~~~
head
foo.cc:79:16: error: 'y' was not declared in this scope
Add(x, y), Add(y, x);
^
自豪的采用HydroJudge(https://github.com/hydro-dev/Hydro)进行评测。