Creating/outputing a binary tree(not BST) - c++

Question

My code (below) works unless the required key isn't in the list yet (so if a node doesn't have a reference to its parent). It ignores the nodes and just makes a tree without them. How can I fix it? I'm thinking about just re-looping once all the keys are in and just keep adding and removing accordingly.
#include <iostream>
#include <string>
#include <sstream>
#include <memory>
#include <map>
struct Foo {
int data{0};
int left{-1};
int right{-1};
};
std::istream& operator>>(std::istream& in, Foo& ff) {
in >> ff.data >> ff.left >> ff.right;
return in;
}
struct Del {
template <class T>
void operator()(T* p) {
std::cout << "[deleted #" << (p ? p->data : 0) << "]\n";
delete p;
}
};
struct Bar {
int data{0};
std::unique_ptr<Bar, Del> lef;
std::unique_ptr<Bar, Del> rig;
};
void print(const std::unique_ptr<Bar, Del>& node) {
if (node) {
std::cout << ' ' << node->data;
print(node->lef);
print(node->rig);
}
}
int main() {
std::string input =
"101 1 3 102 2 8 104 6 7 103 -1 5 109 -1 -1 106 4 -1 107 -1 -1 108 -1 "
"-1 105 -1 -1";
std::istringstream IN(input);
std::map<int, std::pair<Bar*, bool>> mlist;
std::unique_ptr<Bar, Del> root;
int row = 0;
Foo entry;
while (IN >> entry) {
if (0 == row) {
root.reset(new Bar);
Bar* node = root.get();
node->data = entry.data;
std::cout << row << " [created #" << entry.data << ']';
if (0 <= entry.left)
mlist.emplace(entry.left, std::make_pair(node, true));
if (0 <= entry.right)
mlist.emplace(entry.right, std::make_pair(node, false));
} else {
auto it = mlist.find(row);
if (mlist.end() != it) {
if (it->second.second) {
it->second.first->lef.reset(new Bar);
Bar* node = it->second.first->lef.get();
node->data = entry.data;
std::cout << row << " [created #" << entry.data << ']';
if (0 <= entry.left)
mlist.emplace(entry.left, std::make_pair(node, true));
if (0 <= entry.right)
mlist.emplace(entry.right, std::make_pair(node, false));
mlist.erase(it);
} else {
it->second.first->rig.reset(new Bar);
Bar* node = it->second.first->rig.get();
node->data = entry.data;
std::cout << row << " [created #" << entry.data << ']';
if (0 <= entry.left)
mlist.emplace(entry.left, std::make_pair(node, true));
if (0 <= entry.right)
mlist.emplace(entry.right, std::make_pair(node, false));
mlist.erase(it);
}
// mlist.erase( it );
}
}
std::cout << " list size " << mlist.size() << '\n';
++row;
}
std::cout << "final list size " << mlist.size() << "\n\n";
print(root);
std::cout << "\n\n";
std::cout << "Lets see whats left in the list:";
return 0;
}

Answer 1

Actually, I just used a vector of nodes and it worked perfectly. Sorry for all the confusion!