View Compilation Error

0_0_36581691_25824.cpp: In function 'void solve()':
0_0_36581691_25824.cpp:103:20: error: 'add' was not declared in this scope
             add(w,x);
                    ^
0_0_36581691_25824.cpp:106:13: error: 'pre' was not declared in this scope
             pre=query(m);
             ^
0_0_36581691_25824.cpp:106:24: error: 'query' was not declared in this scope
             pre=query(m);
                        ^