View Compilation Error

0_0_35284289_26142.cpp: In function 'int main()':
0_0_35284289_26142.cpp:76:23: error: 'pos' was not declared in this scope
                 debug(pos);
                       ^
0_0_35284289_26142.cpp:16:33: note: in definition of macro 'debug'
 #define debug(x) cerr<<#x<<":"<<x<<endl
                                 ^