Submission #1182739

#	Time	Username	Problem	Language	Result	Execution time	Memory
1182739		SmuggingSpun	Railway Trip 2 (JOI22_ho_t4)	C++20	100 / 100	467 ms	51944 KiB

Main

#include<bits/stdc++.h>
#define taskname "D"
using namespace std;
const int INF = 1e9;
template<class T>void minimize(T& a, T b){
    if(a > b){
        a = b;
    }
}
template<class T>void maximize(T& a, T b){
    if(a < b){
        a = b;
    }
}
int n, k, m, q;
namespace sub1{
    void solve(){
        vector<vector<int>>d(n + 1, vector<int>(n + 1, INF));
        for(int i = 1; i <= n; i++){
            d[i][i] = 0;
        }
        for(int i = 0; i < m; i++){
            int a, b;
            cin >> a >> b;
            if(a < b){
                for(int i = min(b, a + k) - 1; i >= a; i--){
                    for(int j = b; j > i; j--){
                        d[i][j] = 1;
                    }      
                }
            }
            else{
                for(int i = max(b, a - k) + 1; i <= a; i++){
                    for(int j = b; j < i; j++){
                        d[i][j] = 1;
                    }
                }
            }
        }
        for(int k = 1; k <= n; k++){
            for(int u = 1; u <= n; u++){
                for(int v = 1; v <= n; v++){
                    minimize(d[u][v], d[u][k] + d[k][v]);
                }
            }
        }
        cin >> q;
        for(int _ = 0; _ < q; _++){
            int s, t;
            cin >> s >> t;
            cout << (d[s][t] == INF ? -1 : d[s][t]) << "\n";
        }
    }
}
namespace sub2{
    void solve(){
        vector<int>left(n + 1), right(n + 1);
        for(int i = 1; i <= n; i++){
            left[i] = right[i] = i;
        }
        for(int i = 0; i < m; i++){
            int a, b;
            cin >> a >> b;
            if(a < b){
                for(int i = min(b, a + k) - 1; i >= a; i--){
                    maximize(right[i], b);
                }
            }
            else{
                for(int i = max(b, a - k) + 1; i <= a; i++){
                    minimize(left[i], b);
                }
            }
        }
        cin >> q;
        for(int _ = 0; _ < q; _++){
            int s, t;
            cin >> s >> t;
            int l = s, r = s, next_l = left[s], next_r = right[s], ans = -1;
            for(int i = 1; l != next_l || r != next_r; i++){
                int temp_next_l = next_l, temp_next_r = next_r;
                for(int j = temp_next_l; j < l; j++){
                    minimize(next_l, left[j]);
                    maximize(next_r, right[j]);
                }
                for(int j = temp_next_r; j > r; j--){
                    minimize(next_l, left[j]);
                    maximize(next_r, right[j]);
                }
                r = temp_next_r;
                if((l = temp_next_l) <= t && r >= t){
                    ans = i;
                    break;
                }
            }
            cout << ans << "\n";
        }
    }
}
namespace sub3456{
    const int lim = 2e5 + 5;
    pair<int, int>merge(pair<int, int>a, pair<int, int>b){
        return make_pair(min(a.first, b.first), max(a.second, b.second));
    }
    struct SegmentTree{
        pair<int, int>st[lim << 2];        
        pair<int, int>get(int u, int v, int id = 1, int l = 1, int r = n){
            if(l > v || r < u){
                return make_pair(n + 1, -1);
            }
            if(u <= l && v >= r){
                return st[id];
            }
            int m = (l + r) >> 1;
            return merge(get(u, v, id << 1, l, m), get(u, v, id << 1 | 1, m + 1, r));
        }
    };
    SegmentTree up[18];
    pair<int, int>current_range[lim];
    vector<int>event[lim];
    void build(const int layer, int id = 1, int l = 1, int r = n){
        if(l == r){
            up[layer].st[id] = current_range[l];
            return;
        }
        int m = (l + r) >> 1;
        build(layer, id << 1, l, m);
        build(layer, id << 1 | 1, m + 1, r);
        up[layer].st[id] = merge(up[layer].st[id << 1], up[layer].st[id << 1 | 1]);
    }
    void solve(){
        for(int _ = 0; _ < m; _++){
            int a, b;
            cin >> a >> b;
            if(a < b){
                event[a].emplace_back(b);
                event[min(a + k, b)].emplace_back(-b);
            }
            else{
                event[max(a - k, b) + 1].emplace_back(b);
                event[a + 1].emplace_back(-b);
            }
        }
        multiset<int>S;
        for(int i = 1; i <= n; i++){
            for(int& x : event[i]){
                if(x > 0){
                    S.insert(x);
                }
                else{
                    S.erase(S.find(-x));
                }
            }
            current_range[i] = make_pair(min(i, S.empty() ? i : *S.begin()), max(i, S.empty() ? i : *S.rbegin()));
        }
        build(0);
        for(int i = 1; i < 18; i++){
            for(int j = 1; j <= n; j++){
                current_range[j] = up[i - 1].get(current_range[j].first, current_range[j].second);
            }
            build(i);
        }
        cin >> q;
        for(int _ = 0; _ < q; _++){
            int s, t, ans = 0;
            cin >> s >> t;
            for(int i = 17, L = s, R = s; i > -1; i--){
                auto [nl, nr] = up[i].get(L, R);
                if(nl > t || nr < t){
                    L = nl;
                    R = nr;
                    ans |= 1 << i;
                }
            }
            cout << (ans == (1 << 18) - 1 ? -1 : ans + 1) << "\n";
        }
    }
}
int main(){
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	if(fopen(taskname".inp", "r")){
		freopen(taskname".inp", "r", stdin);
	}
    cin >> n >> k >> m;
    if(max(n, m) <= 300){
        sub1::solve();
    }
    else if(max(n, m) <= 2000){
        sub2::solve();
    }
    else{
        sub3456::solve();
    }
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:182:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  182 |                 freopen(taskname".inp", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

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