unsigned long long countSubstrings(SuffixTree &tree, unsigned int v) {
    tree.checkNode(tree[v]);
    unsigned long long sum = tree[v].lengthOfEdge(tree);
    for (auto const &u: tree[v]) {
        sum += countSubstrings(tree, u);
    }
    return sum;
}
void checkDfs(const SuffixTree &tree, unsigned int v, const vector<int> &input
) {
    #ifdef _PRINT_DBG
        printf("%d -> %d [label=\"", tree[v].parent, v);
        for (int i = tree[v].indexOfParentEdge;
            i != tree[v].lastIndex(tree); ++i) {
            printf("%d", input[i]);
        }
        printf(", %d, %d\"]\n", tree[v].leaf, tree[v].depth);
    #endif

    tree.checkNode(tree[v]);
    for (auto const &u: tree[v]) {
        checkDfs(tree, u, input);
    }
}
int decompressDfs(unsigned int v, unsigned int inParentIndex, SuffixTree &tree,
    const vector <int> &input, unsigned int depth
) {
    int leaf = -1;
    unsigned int oldDepth = tree[v].depth;
    tree[v].depth = depth;

    for (unsigned int i = 0; i < tree[v].size(); ++i) {
        unsigned int u = tree[v][i];
        int newLeaf = decompressDfs(u, i, tree, input,
            depth + tree[u].lengthOfEdge(tree, oldDepth) * 2
            - (tree[u].lastIndex(tree, oldDepth) == input.size() / 2 + 1)
        );
        if (leaf == -1) {
            leaf = newLeaf;
        }
    }
    tree[v].indexOfParentEdge *= 2;
    if (tree[v].leaf != -1) {
        tree[v].leaf = min(tree[v].leaf * 2, static_cast<int>(input.size()));
    }

    vector <unsigned int> myNewChildren;
    if (tree[v].size()) {
        vector <unsigned int> similarKids;
        unsigned int firstKidIndex = 0;
        similarKids.push_back(tree[v][0]);
        for (unsigned int i = 1; i <= tree[v].size(); ++i) {
            if (i != tree[v].size()) {
                unsigned int current = tree[v][i];
                unsigned int previous = tree[v][i - 1];
                while (i < tree[v].size()
                    && input[tree[current].indexOfParentEdge]
                        == input[tree[previous].indexOfParentEdge]
                ) {
                    similarKids.push_back(current);
                    ++i;
                    previous = current;
                    if (i != tree[v].size()) {
                        current = tree[v][i];
                    }
                }
            }
            if (similarKids.size() != 1) {
                unsigned int newNodeIndex = tree.splitEdge(v, firstKidIndex, 1);
                auto &newNode = tree[newNodeIndex];
                for (unsigned int j = 1; j < similarKids.size(); ++j) {
                    auto &currentChild = tree[similarKids[j]];
                    currentChild.parent = newNodeIndex;
                    ++currentChild.indexOfParentEdge;
                    newNode.push_back(similarKids[j]);
                }
                if (newNode.size()
                    && tree[newNode[0]].lengthOfEdge(tree) == 0
                ) {
                    newNode.leaf = tree[newNode[0]].leaf;
                    tree.deleteUselessNode(newNode[0], 0, newNode.leaf);
                    newNode.deleteFirstChild();
                }
                myNewChildren.push_back(newNodeIndex);

                tree.checkNode(tree[newNodeIndex]);
            } else {
                myNewChildren.push_back(similarKids.back());
            }
            if (i != tree[v].size()) {
                similarKids.clear();
                similarKids.push_back(tree[v][i]);
                firstKidIndex = i;
            }
        }
    }
    tree[v].renewChildren(myNewChildren);
    if (tree[v].size() == 1 && v != tree.root && tree[v].leaf == -1) {
        tree.deleteUselessNode(v, inParentIndex, leaf);
    }
    if (tree[v].leaf != -1) {
        leaf = tree[v].leaf;
    }
    return leaf;
}