Submission #2414834

---

Source Code Expand

#include <bits/stdc++.h>
using namespace std;
using P = pair<int, int>;
 
int main()
{
    int N;
    cin >> N;
    char c;
    vector<int> x(N), y(N), d(N);
    map<int, set<P>> mp1, mp2;
    for (int i = 0; i < N; i++) {
        cin >> x[i] >> y[i] >> c;
        mp1[x[i]].insert(P(y[i], i));
        mp2[y[i]].insert(P(x[i], i));
 
        d[i] = c == '>' ? 0 : c == '^' ? 1 : c == '<' ? 2 : 3;
    }
    int res = 0;
    for (int i = 0; i < N; i++) {
        auto t1 = mp1;
        auto t2 = mp2;
        int p = i;
        int cnt = 0;
        while (1) {
            t1[x[p]].erase(P(y[p], p));
            t2[y[p]].erase(P(x[p], p));
            cnt++;
            if (d[p] == 3) {
                auto ite = t1[x[p]].lower_bound(P(y[p], 0));
                if (t1[x[p]].empty() || ite == t1[x[p]].end()) {
                    break;
                }
                p = ite->second;
            }
            else if (d[p] == 0) {
                auto ite = t2[y[p]].lower_bound(P(x[p], 0));
                if (t2[y[p]].empty() || ite == t2[y[p]].end()) {
                    break;
                }
                p = ite->second;
            }
            else if (d[p] == 1) {
                auto ite = t1[x[p]].upper_bound(P(y[p], 1e9));
                if (t1[x[p]].empty() || ite-- == t1[x[p]].begin()) {
                    break;
                }
                p = ite->second;
            }
            else {
                auto ite = t2[y[p]].upper_bound(P(x[p], 1e9));
                if (t2[y[p]].empty() || ite-- == t2[y[p]].begin()) {
                    break;
                }
                p = ite->second;
            }
        }
        res = max(res, cnt);
    }
    cout << res << endl;
    return 0;
}

Submission Info

Judge Result