#include <iostream>
#include <string>
#include <vector>

using tree_t = std::vector<std::string>;

struct pt {
    size_t x, y;
};

bool valid(const tree_t& tree, const pt p) {
    if (p.y >= tree.size()) return false;
    if (p.x >= tree[p.y].size()) return false;
    return true;
}

pt go_left(const pt p, size_t i) { return {p.x - i, p.y + i}; }
pt go_right(const pt p, size_t i) { return {p.x + i, p.y + i}; }
char at(const tree_t& tree, const pt p) { return tree[p.y][p.x]; }

bool has_left_child(const tree_t& tree, const pt p) {
    return valid(tree, go_left(p, 1)) && at(tree, go_left(p, 1)) == '/' &&
           valid(tree, go_left(p, 2));
}

bool has_right_child(const tree_t& tree, const pt p) {
    return valid(tree, go_right(p, 1)) && at(tree, go_right(p, 1)) == '\\' &&
           valid(tree, go_right(p, 2));
}

pt root(const tree_t& tree) {
    size_t root = -1;
    for (size_t i = 0; i < tree.front().size(); i++) {
        if (tree.front()[i] != ' ') {
            root = i;
        }
    }
    return {root, 0};
}

void dfs(const tree_t& tree, pt p, std::string& my_stack,
         std::string& solution) {
    bool has_child = false;
    my_stack += at(tree, p);
    if (has_left_child(tree, p)) {
        has_child = true;
        dfs(tree, go_left(p, 2), my_stack, solution);
    }
    if (has_right_child(tree, p)) {
        has_child = true;
        dfs(tree, go_right(p, 2), my_stack, solution);
    }
    if (!has_child) {
        if (solution.back() == ']') {
            solution += ", ";
        }
        solution += "[";

        for (char c : my_stack) {
            solution += c;
            solution += ", ";
        }
        solution.pop_back();
        solution.back() = ']';
    }
    my_stack.pop_back();
}

std::string solution(const tree_t& tree) {
    pt r = root(tree);
    std::string my_stack = "";
    std::string solution = "[";
    dfs(tree, r, my_stack, solution);
    solution += "]";
    return solution;
}

int main() {
    // clang-format off
    const tree_t tree = {
        "   1",
        "  / \\",
        " 2   3",
        "    / \\",
        "   4   5"
    };
    // clang-format on
    std::cout << solution(tree) << std::endl;
}