답안 #935664

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
935664	2024-02-29T10:55:03 Z	peterandvoi	Event Hopping (BOI22_events)	C++17	100 / 100	136 ms	13684 KB

events

#include <bits/stdc++.h>

using namespace std;

#ifdef ngu
#include "debug.h"
#else
#define debug(...) 42
#endif

#define MASK(x) (1LL << (x))

const int N = (int) 1e5 + 5;
const int LOG = 17;

int n, m, q;
pair<int, int> event[N];
int up[LOG][N];

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    #ifdef ngu
    freopen("test.inp", "r", stdin);
    freopen("test.out", "w", stdout);
    #endif
    cin >> n >> q;
    vector<int> R;
    for (int i = 1; i <= n; ++i) {
        cin >> event[i].first >> event[i].second;
        R.emplace_back(event[i].second);
    }
    auto cmb = [&](int x, int y) {
        if (x == -1) {
            return y;
        }
        if (y == -1) {
            return x;
        }
        return event[x].first < event[y].first ? x : y;
    };
    sort(R.begin(), R.end());
    R.erase(unique(R.begin(), R.end()), R.end());
    m = (int) R.size();
    vector<int> tree(4 << __lg(m), -1);
    auto upd = [&](int i, int x) {
        int id = 1, l = 1, r = m;
        while (l < r) {
            int mid = l + r >> 1;
            id <<= 1;
            if (i <= mid) {
                r = mid;
            } else {
                id |= 1;
                l = mid + 1;
            }
        }
        tree[id] = cmb(tree[id], x);
        while (id > 1) {
            id >>= 1;
            tree[id] = cmb(tree[id << 1], tree[id << 1 | 1]);
        }
    };
    auto get = [&](auto get, int u, int v, int id = 1, int l = 1, int r = m) {
        if (u <= l && r <= v) {
            return tree[id];
        }
        int mid = l + r >> 1;
        if (u <= mid && mid < v) {
            return cmb(get(get, u, v, id << 1, l, mid), get(get, u, v, id << 1 | 1, mid + 1, r));
        }
        if (u <= mid) {
            return get(get, u, v, id << 1, l, mid);
        }
        return get(get, u, v, id << 1 | 1, mid + 1, r);
    };
    for (int i = 1; i <= n; ++i) {
        int tr = upper_bound(R.begin(), R.end(), event[i].second) - R.begin();
        upd(tr, i);
    }
    for (int i = 1; i <= n; ++i) {
        int L = lower_bound(R.begin(), R.end(), event[i].first) - R.begin() + 1;
        int tr = upper_bound(R.begin(), R.end(), event[i].second) - R.begin();
        up[0][i] = get(get, L, tr);
    }
    for (int j = 1; j < LOG; ++j) {
        for (int i = 1; i <= n; ++i) {
            up[j][i] = up[j - 1][up[j - 1][i]];
        }
    }
    auto reach = [&](int u, int v) {
        if (v == -1) {
            return false;
        }
        return event[v].first <= event[u].second && event[u].second <= event[v].second;
    };
    auto qry = [&](int s, int t) {
        if (t == s) {
            cout << 0 << "\n";
            return;
        }
        if (event[s].second > event[t].second) {
            cout << "impossible\n";
            return;
        }
        if (event[t].first <= event[s].second) {
            cout << (reach(s, t) ? "1" : "impossible") << "\n";
            return;
        }
        int res = 0;
        for (int i = LOG - 1; i >= 0; --i) {
            int u = up[i][t];
            if (u != -1 && event[u].first > event[s].second) {
                t = u;
                res += MASK(i);
            }
        }
        t = up[0][t];
        if (reach(s, t)) {
            cout << res + 2 << "\n";
        } else {
            cout << "impossible\n";
        }
    };
    while (q--) {
        int s, t;
        cin >> s >> t;
        qry(s, t);
    }
}

Compilation message

events.cpp: In lambda function:
events.cpp:49:25: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   49 |             int mid = l + r >> 1;
      |                       ~~^~~
events.cpp: In instantiation of 'main()::<lambda(auto:23, int, int, int, int, int)> [with auto:23 = main()::<lambda(auto:23, int, int, int, int, int)>]':
events.cpp:84:34:   required from here
events.cpp:68:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   68 |         int mid = l + r >> 1;
      |                   ~~^~~

Subtask #1

10.0 / 10.0

#	결과	실행 시간	메모리	Grader output
1	Correct	1 ms	6492 KB	Output is correct
2	Correct	102 ms	13140 KB	Output is correct
3	Correct	119 ms	13032 KB	Output is correct
4	Correct	118 ms	12900 KB	Output is correct
5	Correct	113 ms	13184 KB	Output is correct
6	Correct	117 ms	13148 KB	Output is correct
7	Correct	114 ms	13136 KB	Output is correct
8	Correct	115 ms	13416 KB	Output is correct
9	Correct	125 ms	13512 KB	Output is correct
10	Correct	109 ms	13428 KB	Output is correct
11	Correct	111 ms	13684 KB	Output is correct
12	Correct	65 ms	12304 KB	Output is correct

Subtask #2

10.0 / 10.0

#	결과	실행 시간	메모리	Grader output
1	Correct	1 ms	6492 KB	Output is correct
2	Correct	1 ms	6492 KB	Output is correct
3	Correct	2 ms	6492 KB	Output is correct
4	Correct	2 ms	6492 KB	Output is correct
5	Correct	2 ms	6492 KB	Output is correct
6	Correct	2 ms	6492 KB	Output is correct
7	Correct	2 ms	6672 KB	Output is correct
8	Correct	2 ms	6488 KB	Output is correct
9	Correct	2 ms	6492 KB	Output is correct

Subtask #3

15.0 / 15.0

#	결과	실행 시간	메모리	Grader output
1	Correct	1 ms	6492 KB	Output is correct
2	Correct	1 ms	6492 KB	Output is correct
3	Correct	2 ms	6492 KB	Output is correct
4	Correct	2 ms	6492 KB	Output is correct
5	Correct	2 ms	6492 KB	Output is correct
6	Correct	2 ms	6492 KB	Output is correct
7	Correct	2 ms	6672 KB	Output is correct
8	Correct	2 ms	6488 KB	Output is correct
9	Correct	2 ms	6492 KB	Output is correct
10	Correct	1 ms	6488 KB	Output is correct
11	Correct	1 ms	6492 KB	Output is correct
12	Correct	2 ms	6492 KB	Output is correct
13	Correct	2 ms	6488 KB	Output is correct
14	Correct	2 ms	6492 KB	Output is correct
15	Correct	2 ms	6492 KB	Output is correct
16	Correct	2 ms	6620 KB	Output is correct
17	Correct	2 ms	6492 KB	Output is correct
18	Correct	2 ms	6492 KB	Output is correct
19	Correct	26 ms	8284 KB	Output is correct
20	Correct	33 ms	8172 KB	Output is correct
21	Correct	27 ms	8528 KB	Output is correct
22	Correct	22 ms	8540 KB	Output is correct
23	Correct	20 ms	8352 KB	Output is correct
24	Correct	18 ms	8284 KB	Output is correct
25	Correct	23 ms	8016 KB	Output is correct

Subtask #4

15.0 / 15.0

#	결과	실행 시간	메모리	Grader output
1	Correct	1 ms	6492 KB	Output is correct
2	Correct	1 ms	6492 KB	Output is correct
3	Correct	2 ms	6492 KB	Output is correct
4	Correct	2 ms	6492 KB	Output is correct
5	Correct	2 ms	6492 KB	Output is correct
6	Correct	2 ms	6492 KB	Output is correct
7	Correct	2 ms	6672 KB	Output is correct
8	Correct	2 ms	6488 KB	Output is correct
9	Correct	2 ms	6492 KB	Output is correct
10	Correct	1 ms	6492 KB	Output is correct
11	Correct	1 ms	6492 KB	Output is correct
12	Correct	2 ms	6488 KB	Output is correct
13	Correct	2 ms	6488 KB	Output is correct
14	Correct	2 ms	6624 KB	Output is correct
15	Correct	2 ms	6492 KB	Output is correct
16	Correct	2 ms	6748 KB	Output is correct
17	Correct	1 ms	6492 KB	Output is correct
18	Correct	1 ms	6492 KB	Output is correct
19	Correct	81 ms	11324 KB	Output is correct
20	Correct	79 ms	10516 KB	Output is correct
21	Correct	83 ms	10696 KB	Output is correct
22	Correct	82 ms	11220 KB	Output is correct
23	Correct	77 ms	11144 KB	Output is correct
24	Correct	90 ms	11216 KB	Output is correct
25	Correct	17 ms	9428 KB	Output is correct

Subtask #5

20.0 / 20.0

#	결과	실행 시간	메모리	Grader output
1	Correct	99 ms	13008 KB	Output is correct
2	Correct	110 ms	13136 KB	Output is correct
3	Correct	121 ms	12988 KB	Output is correct
4	Correct	112 ms	13584 KB	Output is correct
5	Correct	110 ms	13424 KB	Output is correct
6	Correct	115 ms	13240 KB	Output is correct
7	Correct	115 ms	13176 KB	Output is correct
8	Correct	112 ms	13404 KB	Output is correct
9	Correct	80 ms	11128 KB	Output is correct
10	Correct	112 ms	12888 KB	Output is correct
11	Correct	113 ms	12508 KB	Output is correct
12	Correct	118 ms	12728 KB	Output is correct

Subtask #6

30.0 / 30.0

#	결과	실행 시간	메모리	Grader output
1	Correct	1 ms	6492 KB	Output is correct
2	Correct	102 ms	13140 KB	Output is correct
3	Correct	119 ms	13032 KB	Output is correct
4	Correct	118 ms	12900 KB	Output is correct
5	Correct	113 ms	13184 KB	Output is correct
6	Correct	117 ms	13148 KB	Output is correct
7	Correct	114 ms	13136 KB	Output is correct
8	Correct	115 ms	13416 KB	Output is correct
9	Correct	125 ms	13512 KB	Output is correct
10	Correct	109 ms	13428 KB	Output is correct
11	Correct	111 ms	13684 KB	Output is correct
12	Correct	65 ms	12304 KB	Output is correct
13	Correct	1 ms	6492 KB	Output is correct
14	Correct	1 ms	6492 KB	Output is correct
15	Correct	2 ms	6492 KB	Output is correct
16	Correct	2 ms	6492 KB	Output is correct
17	Correct	2 ms	6492 KB	Output is correct
18	Correct	2 ms	6492 KB	Output is correct
19	Correct	2 ms	6672 KB	Output is correct
20	Correct	2 ms	6488 KB	Output is correct
21	Correct	2 ms	6492 KB	Output is correct
22	Correct	1 ms	6488 KB	Output is correct
23	Correct	1 ms	6492 KB	Output is correct
24	Correct	2 ms	6492 KB	Output is correct
25	Correct	2 ms	6488 KB	Output is correct
26	Correct	2 ms	6492 KB	Output is correct
27	Correct	2 ms	6492 KB	Output is correct
28	Correct	2 ms	6620 KB	Output is correct
29	Correct	2 ms	6492 KB	Output is correct
30	Correct	2 ms	6492 KB	Output is correct
31	Correct	26 ms	8284 KB	Output is correct
32	Correct	33 ms	8172 KB	Output is correct
33	Correct	27 ms	8528 KB	Output is correct
34	Correct	22 ms	8540 KB	Output is correct
35	Correct	20 ms	8352 KB	Output is correct
36	Correct	18 ms	8284 KB	Output is correct
37	Correct	23 ms	8016 KB	Output is correct
38	Correct	1 ms	6492 KB	Output is correct
39	Correct	1 ms	6492 KB	Output is correct
40	Correct	2 ms	6488 KB	Output is correct
41	Correct	2 ms	6488 KB	Output is correct
42	Correct	2 ms	6624 KB	Output is correct
43	Correct	2 ms	6492 KB	Output is correct
44	Correct	2 ms	6748 KB	Output is correct
45	Correct	1 ms	6492 KB	Output is correct
46	Correct	1 ms	6492 KB	Output is correct
47	Correct	81 ms	11324 KB	Output is correct
48	Correct	79 ms	10516 KB	Output is correct
49	Correct	83 ms	10696 KB	Output is correct
50	Correct	82 ms	11220 KB	Output is correct
51	Correct	77 ms	11144 KB	Output is correct
52	Correct	90 ms	11216 KB	Output is correct
53	Correct	17 ms	9428 KB	Output is correct
54	Correct	99 ms	13008 KB	Output is correct
55	Correct	110 ms	13136 KB	Output is correct
56	Correct	121 ms	12988 KB	Output is correct
57	Correct	112 ms	13584 KB	Output is correct
58	Correct	110 ms	13424 KB	Output is correct
59	Correct	115 ms	13240 KB	Output is correct
60	Correct	115 ms	13176 KB	Output is correct
61	Correct	112 ms	13404 KB	Output is correct
62	Correct	80 ms	11128 KB	Output is correct
63	Correct	112 ms	12888 KB	Output is correct
64	Correct	113 ms	12508 KB	Output is correct
65	Correct	118 ms	12728 KB	Output is correct
66	Correct	1 ms	6492 KB	Output is correct
67	Correct	98 ms	12996 KB	Output is correct
68	Correct	109 ms	13016 KB	Output is correct
69	Correct	117 ms	13012 KB	Output is correct
70	Correct	121 ms	13008 KB	Output is correct
71	Correct	110 ms	13144 KB	Output is correct
72	Correct	113 ms	13008 KB	Output is correct
73	Correct	123 ms	13408 KB	Output is correct
74	Correct	110 ms	13408 KB	Output is correct
75	Correct	109 ms	13484 KB	Output is correct
76	Correct	136 ms	13452 KB	Output is correct
77	Correct	59 ms	12244 KB	Output is correct
78	Correct	1 ms	6492 KB	Output is correct
79	Correct	2 ms	6492 KB	Output is correct
80	Correct	2 ms	6492 KB	Output is correct
81	Correct	1 ms	6624 KB	Output is correct
82	Correct	2 ms	6492 KB	Output is correct
83	Correct	2 ms	6492 KB	Output is correct
84	Correct	2 ms	6492 KB	Output is correct
85	Correct	1 ms	6664 KB	Output is correct
86	Correct	27 ms	8192 KB	Output is correct
87	Correct	24 ms	8280 KB	Output is correct
88	Correct	27 ms	8544 KB	Output is correct
89	Correct	21 ms	8404 KB	Output is correct
90	Correct	20 ms	8280 KB	Output is correct
91	Correct	18 ms	8332 KB	Output is correct
92	Correct	22 ms	7960 KB	Output is correct
93	Correct	82 ms	11148 KB	Output is correct
94	Correct	79 ms	10352 KB	Output is correct
95	Correct	86 ms	10704 KB	Output is correct
96	Correct	87 ms	11324 KB	Output is correct
97	Correct	80 ms	11220 KB	Output is correct
98	Correct	93 ms	11300 KB	Output is correct
99	Correct	17 ms	9700 KB	Output is correct
100	Correct	118 ms	13156 KB	Output is correct
101	Correct	125 ms	13308 KB	Output is correct
102	Correct	115 ms	13352 KB	Output is correct
103	Correct	123 ms	13184 KB	Output is correct
104	Correct	130 ms	12500 KB	Output is correct
105	Correct	112 ms	12804 KB	Output is correct
106	Correct	101 ms	12504 KB	Output is correct
107	Correct	131 ms	12692 KB	Output is correct
108	Correct	106 ms	12752 KB	Output is correct
109	Correct	103 ms	12520 KB	Output is correct
110	Correct	119 ms	13032 KB	Output is correct
111	Correct	115 ms	13008 KB	Output is correct