Submission #42299

#	Time	Username	Problem	Language	Result	Execution time	Memory
42299		minhtung0404	버스 (JOI14_bus)	C++14	100 / 100	606 ms	262144 KiB

bus

#include<bits/stdc++.h>
const int N = 1e5 + 5;
const int M = 3e5 + 5;
const int inf = 1e9 + 7;
using namespace std;

vector <int> mv, adj[N], Min[N];
int n, m, q, num, a[M], b[M], x[M], y[M], dp[M];

bool cmp(int i, int j){
    if (y[i] > y[j]) return false;
    if (y[i] == y[j] && x[i] > x[j]) return false;
    return true;
}

int main(){
    ios::sync_with_stdio(false);
    cin >> n >> m;
    for (int i = 1; i <= m; i++){
        cin >> a[i] >> b[i] >> x[i] >> y[i];
        mv.push_back(i);
        adj[b[i]].push_back(i);
    }
    sort(mv.begin(), mv.end(), cmp);
    for (int i = 1; i <= n; i++) sort(adj[i].begin(), adj[i].end(), cmp);
    for (int ed = 0; ed < m; ed++){
        int i = mv[ed], u = a[i], v = b[i];
        if (u == 1) dp[ed] = x[i];
        else if (adj[u].size() == 0) dp[ed] = -inf;
        else{
            int l = 0, r = adj[u].size()-1;
            while (l != r){
                int mid = (l + r + 1) / 2;
                if (y[adj[u][mid]] <= x[i]) l = mid;
                else r = mid-1;
            }
            if (y[adj[u][l]] > x[i]) dp[ed] = -inf;
            else dp[ed] = Min[u][l];
        }
        if (Min[v].size() == 0) Min[v].push_back(dp[ed]);
        else Min[v].push_back(max(dp[ed], *Min[v].rbegin()));
    }
    cin >> q;
    while (q--){
        cin >> num;
        if (adj[n].size() == 0) cout << "-1\n";
        else{
            int l = 0, r = adj[n].size()-1;
            while (l != r){
                int mid = (l + r + 1)/ 2;
                if (y[adj[n][mid]] <= num) l = mid;
                else r = mid-1;
            }
            if (y[adj[n][l]] <= num && Min[n][l] != -inf) cout << Min[n][l] << "\n";
            else cout << "-1\n";
        }
    }
}

• Subtask 1: 20 / 20
• Subtask 2: 15 / 15
• Subtask 3: 15 / 15
• Subtask 4: 50 / 50