View Compilation Error

0_0_22114934_18284.cpp: In member function 'void Node::pushdown()':
0_0_22114934_18284.cpp:24:33: error: 'swap' was not declared in this scope
                 swap(ch[0],ch[1]);
                                 ^
0_0_22114934_18284.cpp: In member function 'void SplayTree::print(Node*)':
0_0_22114934_18284.cpp:113:52: error: 'printf' was not declared in this scope
             printf("%d%c",o->v," \n"[++ansCount==n]);
                                                    ^
0_0_22114934_18284.cpp: In function 'int main()':
0_0_22114934_18284.cpp:154:29: error: 'scanf' was not declared in this scope
     while(scanf("%d%d",&n,&m)!=EOF){
                             ^
0_0_22114934_18284.cpp:154:32: error: 'EOF' was not declared in this scope
     while(scanf("%d%d",&n,&m)!=EOF){
                                ^