Submission #863880

#	Time	Username	Problem	Language	Result	Execution time	Memory
863880		prairie2022	Railway Trip 2 (JOI22_ho_t4)	C++17	11 / 100	2058 ms	10708 KiB

Main

#include<bits/stdc++.h>
typedef long long ll;
#define fastio cin.tie(0), cout.tie(0), ios::sync_with_stdio(0);
using namespace std;

#define pii pair<int, int>
#define F first 
#define S second

inline bool between(int b, int a, int c){
    if(a<=b && b<=c) return 1;
    if(a>=b && b>=c) return 1;
    return 0;
}

int k;
inline int near(int s, pii p){
    if(between(s, p.F, p.S)){
        if(abs(s-p.F)<k) return s;
        if(p.F<s) return p.F+k-1;
        if(p.F>s) return p.F-k+1;
    }
    if(between(p.F, s, p.S)) return p.F;
    return 0;
}

int main(){
    fastio
    int n, m;
    cin >> n >> k >> m;
    vector<pii> rail(m);
    for(int i=0; i<m; i++)
        cin >> rail[i].F >> rail[i].S;
    int q, s, t;
    for(cin >> q; q; q--){
        cin >> s >> t;
        vector<vector<int>> way(n+1);
        for(int i=0; i<m; i++){
            if(near(s, rail[i])) way[near(s, rail[i])].push_back(i);
        }
        vector<int> dp(n+1, -1);
        dp[s] = 0;
        int l = s, r = s;
        queue<int> qu;
        for(qu.push(s); !qu.empty() || qu.front()==t; qu.pop()){
            //cout << qu.front() << " : ";
            for(const int &w: way[qu.front()]){
                //cout << w << ' ';
                if(rail[w].S>r){
                    for(int i=r+1; i<=rail[w].S; i++){
                        dp[i] = dp[qu.front()]+1;
                        qu.push(i);
                    }
                    r = rail[w].S;
                }
                else if(rail[w].S<l){
                    for(int i=l-1; i>=rail[w].S; i--){
                        dp[i] = dp[qu.front()]+1;
                        qu.push(i);
                    }
                    l = rail[w].S;
                }
            }
            //cout << '\n';
        }
        cout << dp[t] << '\n';
    }
    return 0;
}

• Subtask 1: 0 / 8
• Subtask 2: 0 / 8
• Subtask 3: 11 / 11
• Subtask 4: 0 / 25
• Subtask 5: 0 / 35
• Subtask 6: 0 / 13