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

using namespace std;

int main() {
    int reverse_dir[] = {0, 2, 1, 4, 3}; // 1上2下3左4右的反方向映射
    vector<pair<int, int>> path;
    string s;

    while (cin >> s) {
        if (s == "0-0") break;
        
        // 解析输入的方向和距离
        size_t pos = s.find('-');
        int d = stoi(s.substr(0, pos));
        int dist = stoi(s.substr(pos + 1));

        // 抵消反方向路径
        while (dist > 0 && !path.empty()) {
            auto &last = path.back();
            if (last.first == reverse_dir[d]) {
                if (last.second > dist) {
                    last.second -= dist;
                    dist = 0;
                } else if (last.second == dist) {
                    path.pop_back();
                    dist = 0;
                } else {
                    dist -= last.second;
                    path.pop_back();
                }
     ...