View Compilation Error

0_0_24814755_29023.cpp: In member function 'void HJTree::add(int, int&, int, int)':
0_0_24814755_29023.cpp:22:17: error: 'num' was not declared in this scope
   if(val<=m)add(num,v[rt].lc,l,m);
                 ^
0_0_24814755_29023.cpp:23:12: error: 'num' was not declared in this scope
   else add(num,v[rt].rc,m+1,r);
            ^
0_0_24814755_29023.cpp: In function 'int main()':
0_0_24814755_29023.cpp:42:18: error: 'l' was not declared in this scope
    scanf("%d%d",&l,&r);
                  ^
0_0_24814755_29023.cpp:42:21: error: 'r' was not declared in this scope
    scanf("%d%d",&l,&r);
                     ^