답안 #718036

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
718036	2023-04-03T08:23:04 Z	fatemetmhr	Event Hopping (BOI22_events)	C++17	100 / 100	434 ms	37432 KB

events

// Be name khoda //

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

#define all(x) x.begin(), x.end()
#define pb     push_back
#define fi     first
#define se     second
#define mp     make_pair

const int maxn5 = 2e5 + 10;
const int lg    = 19;

vector <int> ch, av, req[maxn5];
int l[maxn5], r[maxn5], ans[maxn5], par[lg][maxn5];
int x[maxn5], y[maxn5], ind[maxn5], per[maxn5];
pair <int, int> fen[maxn5];


inline bool cmp(int i, int j){return r[i] < r[j] || (r[i] == r[j] && l[i] < l[j]);}

inline void max_mos(int id, pair <int, int> val){
    for(++id; id < maxn5; id += id & -id){
        fen[id] = max(fen[id], val);
        ch.pb(id);
    }
}

inline pair <int, int> get_max(int id){
    pair <int, int> ret = {-1, -1};
    for(++id; id; id -= id & -id)
        ret = max(ret, fen[id]);
    return ret;
}

inline void fen_reset(){
    for(auto u : ch)
        fen[u] = {-1, -1};
    ch.clear();
}

void solve(int lq, int rq){
    if(rq - lq == 1)
        return;
    int mid = (lq + rq) >> 1;
    solve(lq, mid);
    int mn = l[per[mid]];
    for(int i = mid; i < rq; i++){ 
        mn = min(mn, l[per[i]]);
        max_mos(l[per[i]], mp(r[per[i]], i));
        for(auto id : req[i]) if(x[id] >= lq && x[id] < mid){
            int v = x[id];
            if(r[per[v]] < mn){
                for(int j = lg - 1; j >= 0; j--) if(par[j][v] != -1 && r[per[par[j][v]]] < mn){
                    v = par[j][v];
                    ans[id] += (1 << j);
                }
                v = par[0][v];
                ans[id]++;
            }
            if(v == -1){
                ans[id] = -1;
                continue;
            }
            //cout << "hey it's " << i << ' ' << id << ' ' << x[id] << ' ' << v << '\n';
            auto mx = get_max(r[per[v]]);
            x[id] = mx.se;
            ans[id]++;
        }
    }
    for(int i = mid - 1; i >= lq; i--){
        for(int j = 0; j < lg; j++)
            par[j][i] = -1;
        par[0][i] = get_max(r[per[i]]).se;
        max_mos(l[per[i]], mp(r[per[i]], i));
    }
    fen_reset();
    solve(mid, rq);
    for(int i = 1; i < lg; i++) for(int v = lq; v < mid; v++)
        if(par[i - 1][v] != -1) par[i][v] = par[i - 1][par[i - 1][v]];
}

int main(){
    ios_base::sync_with_stdio(false); cin.tie(0);

    fill(fen, fen + maxn5, mp(-1, -1));

    int n, q; cin >> n >> q;
    for(int i = 0; i < n; i++){
        cin >> l[i] >> r[i];
        av.pb(l[i]);
        av.pb(r[i]);
        per[i] = i;
    }
    sort(all(av));
    av.resize(unique(all(av)) - av.begin());
    for(int i = 0; i < n; i++){
        l[i] = lower_bound(all(av), l[i]) - av.begin();
        r[i] = lower_bound(all(av), r[i]) - av.begin();
        //cout << i << ' ' << l[i] << ' ' << r[i] << '\n';
    }
    sort(per, per + n, cmp);
    for(int i = 0; i < n; i++)
        ind[per[i]] = i;

    for(int i = 0; i < q; i++){
        cin >> x[i] >> y[i];
        x[i]--; y[i]--;
        if(x[i] == y[i])
            continue;
        if(ind[x[i]] > ind[y[i]])
            ans[i] = r[y[i]] == r[x[i]] ? 1 : -1;
        else{
            req[ind[y[i]]].pb(i);
            x[i] = ind[x[i]];
            y[i] = ind[y[i]];
        }
        //cout << "ok " << i << ' ' << x[i] << ' ' << y[i] << '\n';
    }

    memset(par, -1, sizeof par);

    solve(0, n);
    for(int i = 0; i < q; i++){
        if(ans[i] == -1)
            cout << "impossible\n";
        else
            cout << ans[i] << '\n';
    }
}

/*
5 1
1 3
2 4
4 7
7 9
3 7
1 4

3 2
*/

Subtask #1

10.0 / 10.0

#	결과	실행 시간	메모리	Grader output
1	Correct	10 ms	21460 KB	Output is correct
2	Correct	403 ms	33928 KB	Output is correct
3	Correct	376 ms	33372 KB	Output is correct
4	Correct	348 ms	34208 KB	Output is correct
5	Correct	384 ms	33288 KB	Output is correct
6	Correct	364 ms	33232 KB	Output is correct
7	Correct	397 ms	33224 KB	Output is correct
8	Correct	304 ms	33224 KB	Output is correct
9	Correct	340 ms	33740 KB	Output is correct
10	Correct	366 ms	34140 KB	Output is correct
11	Correct	379 ms	34008 KB	Output is correct
12	Correct	275 ms	33876 KB	Output is correct

Subtask #2

10.0 / 10.0

#	결과	실행 시간	메모리	Grader output
1	Correct	10 ms	21484 KB	Output is correct
2	Correct	10 ms	21460 KB	Output is correct
3	Correct	11 ms	21716 KB	Output is correct
4	Correct	12 ms	21584 KB	Output is correct
5	Correct	12 ms	21576 KB	Output is correct
6	Correct	12 ms	21664 KB	Output is correct
7	Correct	13 ms	21576 KB	Output is correct
8	Correct	12 ms	21580 KB	Output is correct
9	Correct	13 ms	21644 KB	Output is correct

Subtask #3

15.0 / 15.0

#	결과	실행 시간	메모리	Grader output
1	Correct	10 ms	21484 KB	Output is correct
2	Correct	10 ms	21460 KB	Output is correct
3	Correct	11 ms	21716 KB	Output is correct
4	Correct	12 ms	21584 KB	Output is correct
5	Correct	12 ms	21576 KB	Output is correct
6	Correct	12 ms	21664 KB	Output is correct
7	Correct	13 ms	21576 KB	Output is correct
8	Correct	12 ms	21580 KB	Output is correct
9	Correct	13 ms	21644 KB	Output is correct
10	Correct	9 ms	21460 KB	Output is correct
11	Correct	9 ms	21460 KB	Output is correct
12	Correct	11 ms	21588 KB	Output is correct
13	Correct	11 ms	21588 KB	Output is correct
14	Correct	11 ms	21576 KB	Output is correct
15	Correct	12 ms	21568 KB	Output is correct
16	Correct	12 ms	21576 KB	Output is correct
17	Correct	12 ms	21580 KB	Output is correct
18	Correct	14 ms	21640 KB	Output is correct
19	Correct	52 ms	25196 KB	Output is correct
20	Correct	84 ms	25128 KB	Output is correct
21	Correct	63 ms	25212 KB	Output is correct
22	Correct	50 ms	25280 KB	Output is correct
23	Correct	55 ms	25140 KB	Output is correct
24	Correct	50 ms	25116 KB	Output is correct
25	Correct	67 ms	25024 KB	Output is correct

Subtask #4

15.0 / 15.0

#	결과	실행 시간	메모리	Grader output
1	Correct	10 ms	21484 KB	Output is correct
2	Correct	10 ms	21460 KB	Output is correct
3	Correct	11 ms	21716 KB	Output is correct
4	Correct	12 ms	21584 KB	Output is correct
5	Correct	12 ms	21576 KB	Output is correct
6	Correct	12 ms	21664 KB	Output is correct
7	Correct	13 ms	21576 KB	Output is correct
8	Correct	12 ms	21580 KB	Output is correct
9	Correct	13 ms	21644 KB	Output is correct
10	Correct	9 ms	21496 KB	Output is correct
11	Correct	9 ms	21460 KB	Output is correct
12	Correct	11 ms	21588 KB	Output is correct
13	Correct	12 ms	21668 KB	Output is correct
14	Correct	12 ms	21588 KB	Output is correct
15	Correct	11 ms	21580 KB	Output is correct
16	Correct	13 ms	21612 KB	Output is correct
17	Correct	11 ms	21580 KB	Output is correct
18	Correct	11 ms	21716 KB	Output is correct
19	Correct	287 ms	29960 KB	Output is correct
20	Correct	292 ms	29228 KB	Output is correct
21	Correct	340 ms	34004 KB	Output is correct
22	Correct	302 ms	30012 KB	Output is correct
23	Correct	300 ms	30008 KB	Output is correct
24	Correct	309 ms	29980 KB	Output is correct
25	Correct	351 ms	33588 KB	Output is correct

Subtask #5

20.0 / 20.0

#	결과	실행 시간	메모리	Grader output
1	Correct	368 ms	33928 KB	Output is correct
2	Correct	374 ms	33252 KB	Output is correct
3	Correct	359 ms	34180 KB	Output is correct
4	Correct	328 ms	33616 KB	Output is correct
5	Correct	377 ms	34112 KB	Output is correct
6	Correct	363 ms	33848 KB	Output is correct
7	Correct	380 ms	33756 KB	Output is correct
8	Correct	377 ms	33696 KB	Output is correct
9	Correct	314 ms	29908 KB	Output is correct
10	Correct	371 ms	33000 KB	Output is correct
11	Correct	356 ms	32932 KB	Output is correct
12	Correct	370 ms	32952 KB	Output is correct

Subtask #6

30.0 / 30.0

#	결과	실행 시간	메모리	Grader output
1	Correct	10 ms	21460 KB	Output is correct
2	Correct	403 ms	33928 KB	Output is correct
3	Correct	376 ms	33372 KB	Output is correct
4	Correct	348 ms	34208 KB	Output is correct
5	Correct	384 ms	33288 KB	Output is correct
6	Correct	364 ms	33232 KB	Output is correct
7	Correct	397 ms	33224 KB	Output is correct
8	Correct	304 ms	33224 KB	Output is correct
9	Correct	340 ms	33740 KB	Output is correct
10	Correct	366 ms	34140 KB	Output is correct
11	Correct	379 ms	34008 KB	Output is correct
12	Correct	275 ms	33876 KB	Output is correct
13	Correct	10 ms	21484 KB	Output is correct
14	Correct	10 ms	21460 KB	Output is correct
15	Correct	11 ms	21716 KB	Output is correct
16	Correct	12 ms	21584 KB	Output is correct
17	Correct	12 ms	21576 KB	Output is correct
18	Correct	12 ms	21664 KB	Output is correct
19	Correct	13 ms	21576 KB	Output is correct
20	Correct	12 ms	21580 KB	Output is correct
21	Correct	13 ms	21644 KB	Output is correct
22	Correct	9 ms	21460 KB	Output is correct
23	Correct	9 ms	21460 KB	Output is correct
24	Correct	11 ms	21588 KB	Output is correct
25	Correct	11 ms	21588 KB	Output is correct
26	Correct	11 ms	21576 KB	Output is correct
27	Correct	12 ms	21568 KB	Output is correct
28	Correct	12 ms	21576 KB	Output is correct
29	Correct	12 ms	21580 KB	Output is correct
30	Correct	14 ms	21640 KB	Output is correct
31	Correct	52 ms	25196 KB	Output is correct
32	Correct	84 ms	25128 KB	Output is correct
33	Correct	63 ms	25212 KB	Output is correct
34	Correct	50 ms	25280 KB	Output is correct
35	Correct	55 ms	25140 KB	Output is correct
36	Correct	50 ms	25116 KB	Output is correct
37	Correct	67 ms	25024 KB	Output is correct
38	Correct	9 ms	21496 KB	Output is correct
39	Correct	9 ms	21460 KB	Output is correct
40	Correct	11 ms	21588 KB	Output is correct
41	Correct	12 ms	21668 KB	Output is correct
42	Correct	12 ms	21588 KB	Output is correct
43	Correct	11 ms	21580 KB	Output is correct
44	Correct	13 ms	21612 KB	Output is correct
45	Correct	11 ms	21580 KB	Output is correct
46	Correct	11 ms	21716 KB	Output is correct
47	Correct	287 ms	29960 KB	Output is correct
48	Correct	292 ms	29228 KB	Output is correct
49	Correct	340 ms	34004 KB	Output is correct
50	Correct	302 ms	30012 KB	Output is correct
51	Correct	300 ms	30008 KB	Output is correct
52	Correct	309 ms	29980 KB	Output is correct
53	Correct	351 ms	33588 KB	Output is correct
54	Correct	368 ms	33928 KB	Output is correct
55	Correct	374 ms	33252 KB	Output is correct
56	Correct	359 ms	34180 KB	Output is correct
57	Correct	328 ms	33616 KB	Output is correct
58	Correct	377 ms	34112 KB	Output is correct
59	Correct	363 ms	33848 KB	Output is correct
60	Correct	380 ms	33756 KB	Output is correct
61	Correct	377 ms	33696 KB	Output is correct
62	Correct	314 ms	29908 KB	Output is correct
63	Correct	371 ms	33000 KB	Output is correct
64	Correct	356 ms	32932 KB	Output is correct
65	Correct	370 ms	32952 KB	Output is correct
66	Correct	9 ms	21460 KB	Output is correct
67	Correct	383 ms	34008 KB	Output is correct
68	Correct	370 ms	33172 KB	Output is correct
69	Correct	378 ms	34212 KB	Output is correct
70	Correct	368 ms	33308 KB	Output is correct
71	Correct	379 ms	33236 KB	Output is correct
72	Correct	406 ms	33228 KB	Output is correct
73	Correct	361 ms	33448 KB	Output is correct
74	Correct	352 ms	33684 KB	Output is correct
75	Correct	387 ms	34064 KB	Output is correct
76	Correct	408 ms	34000 KB	Output is correct
77	Correct	302 ms	33836 KB	Output is correct
78	Correct	10 ms	21460 KB	Output is correct
79	Correct	12 ms	21588 KB	Output is correct
80	Correct	13 ms	21620 KB	Output is correct
81	Correct	15 ms	21592 KB	Output is correct
82	Correct	14 ms	21580 KB	Output is correct
83	Correct	14 ms	21576 KB	Output is correct
84	Correct	13 ms	21588 KB	Output is correct
85	Correct	12 ms	21716 KB	Output is correct
86	Correct	54 ms	25092 KB	Output is correct
87	Correct	87 ms	25148 KB	Output is correct
88	Correct	87 ms	25216 KB	Output is correct
89	Correct	52 ms	25292 KB	Output is correct
90	Correct	53 ms	25216 KB	Output is correct
91	Correct	47 ms	25160 KB	Output is correct
92	Correct	74 ms	24916 KB	Output is correct
93	Correct	293 ms	29932 KB	Output is correct
94	Correct	295 ms	29128 KB	Output is correct
95	Correct	345 ms	33972 KB	Output is correct
96	Correct	297 ms	29944 KB	Output is correct
97	Correct	337 ms	29976 KB	Output is correct
98	Correct	311 ms	30008 KB	Output is correct
99	Correct	366 ms	33336 KB	Output is correct
100	Correct	381 ms	33872 KB	Output is correct
101	Correct	377 ms	33852 KB	Output is correct
102	Correct	372 ms	33864 KB	Output is correct
103	Correct	354 ms	33064 KB	Output is correct
104	Correct	337 ms	32848 KB	Output is correct
105	Correct	383 ms	32968 KB	Output is correct
106	Correct	392 ms	33360 KB	Output is correct
107	Correct	349 ms	33140 KB	Output is correct
108	Correct	410 ms	37372 KB	Output is correct
109	Correct	387 ms	37432 KB	Output is correct
110	Correct	386 ms	33676 KB	Output is correct
111	Correct	434 ms	33856 KB	Output is correct