Submission #587362

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
587362	2022-07-01T17:25:29 Z	blue	Event Hopping (BOI22_events)	C++17	100 / 100	746 ms	79096 KB

events

#include <iostream>
#include <vector>
#include <algorithm>
#include <set>
#include <map>
#include <stack>
#include <queue>
using namespace std;

using vi = vector<int>;
using vvi = vector<vi>;
using ll = long long;
using vll = vector<ll>;
using vvll = vector<vll>;
using pii = pair<int, int>;
using vpii = vector<pii>;
using pll = pair<ll, ll>;
using vpll = vector<pll>;
#define sz(x) int(x.size())

const int mx = 200'000;
const int lg = 18;

int mxv[1+mx][1+lg];
int bst[1+mx];

int jmp[1+mx][1+lg];

int rangemax(int l, int r)
{
	int z = bst[r-l+1];
	return max(mxv[l][z], mxv[r - (1 << z) + 1][z]);
}


int Z = 262144;
int stree[1+lg][(1<<19)];

int smax(int e, int l, int r)
{
	int ans = 0;
	l += Z;
	r += Z+1;

	while(l < r)
	{
		if(l & 1)
		{
			ans = max(ans, stree[e][l]);
			l++;
		}

		if(r & 1)
		{
			r--;
			ans = max(ans, stree[e][r]);
		}

		r >>= 1;
		l >>= 1;
	}

	return ans;
}

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

	int N, Q;
	cin >> N >> Q;

	map<int, int> norm;

	vi S(1+N), E(1+N);
	for(int i = 1; i <= N; i++)
	{
		cin >> S[i] >> E[i];
		S[i] *= -1;
		E[i] *= -1;
		swap(S[i], E[i]);

		norm[S[i]] = 0;
		norm[E[i]] = 0;
	}

	int ct = 0;	
	for(auto& z : norm)
		z.second = ++ct;

	for(int i = 1; i <= N; i++)
	{
		S[i] = norm[S[i]];
		E[i] = norm[E[i]];
	}

	// cerr << "\n\n";
	// for(int i = 1; i <= N; i++)
	// 	cerr << S[i] << ' ' << E[i] << '\n';
	// cerr << "\n\n";


	for(int i = 0; i <= mx; i++)
		for(int j = 0; j <= lg; j++)
			mxv[i][j] = 0;

	for(int i = 1; i <= N; i++)
		mxv[S[i]][0] = max(mxv[S[i]][0], E[i]);

	for(int e = 1; e <= lg; e++)
	{
		for(int i = 0; i <= mx; i++)
		{
			mxv[i][e] = mxv[i][e-1];
			if(i + (1 << (e-1)) <= mx)
				mxv[i][e] = max(mxv[i][e], mxv[ i + (1 << (e-1)) ][e-1]);
		}
	}

	bst[1] = 0;
	for(int i = 1; i <= mx; i++)
	{
		bst[i] = bst[i-1];
		if((1 << (bst[i]+1)) == i)
			bst[i]++;
	}


	for(int i = 0; i <= mx; i++)
	{
		jmp[i][0] = max(i, mxv[i][0]);
	}

	for(int e = 0; e <= lg; e++)
	{

		if(e > 0)
		{
			for(int i = 0; i <= mx; i++)
			{
				// cerr << i << " : " << jmp[i][e-1];
				if(i > jmp[i][e-1])
				{
					// cerr << e-1 << '\n';
					// cerr << i << " : " << jmp[i][e-1] << '\n';
					while(1);
				}

				jmp[i][e] = 0;
				// for(int h = i; h <= jmp[i][e-1]; h++)
				// 	jmp[i][e] = max(jmp[i][e], jmp[h][e-1]);
				// jmp[i][e] = rangemax(i, jmp[i][e-1]);
				jmp[i][e] = smax(e-1, i, jmp[i][e-1]);
			}
		}
		
		for(int i = 0; i <= mx; i++)
			stree[e][Z+i] = jmp[i][e];

		for(int i = Z-1; i >= 0; i--)
			stree[e][i] = max(stree[e][2*i], stree[e][2*i + 1]);
	}
	// cerr << "check\n";





	for(int q = 1; q <= Q; q++)
	{
		int a, b;
		cin >> a >> b;
		swap(a, b);


		int lt = S[a], rt = E[a];

		if(a == b) 
		{
			cout << "0\n";
			continue;
		}
		else if(S[b] < S[a])
		{
			cout << "impossible\n";
			continue;
		}

		// int tot = 0;
		// for(int i = lt; i <= rt; i++)
		// 	tot = max(tot, jmp[i][lg]);

		int tot = smax(lg, lt, rt);

		if(tot < S[b])
		{
			cout << "impossible\n";
			continue;
		}

		int ans = 0;

		for(int e = lg; e >= 0; e--)
		{	

			// int nrt = 0;
			// for(int i = lt; i <= rt; i++)
			// 	nrt = max(nrt, jmp[i][e]);
			int nrt = smax(e, lt, rt);

			// cerr << "e = " << e << " : ";
			// cerr << lt << ' ' << rt << " -> " << lt << ' ' << nrt << " cmp " << S[b] << '\n';

			if(nrt < S[b])
			{
				rt = nrt;
				ans += (1<<e);
			}
			else if(nrt == S[b])
			{
				rt = nrt;
				ans += (1<<e);
				break;
			}
		}

		if(rt < S[b])
		{
			rt = S[b];
			ans++;
		}

		// cerr << "current lt rt = " << lt << ' ' << rt << '\n';
		ans++;
		
		cout << ans << '\n';
	}


}

Subtask #1

10.0 / 10.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	103 ms	65236 KB	Output is correct
2	Correct	463 ms	71536 KB	Output is correct
3	Correct	411 ms	72256 KB	Output is correct
4	Correct	428 ms	72808 KB	Output is correct
5	Correct	467 ms	73420 KB	Output is correct
6	Correct	470 ms	74728 KB	Output is correct
7	Correct	451 ms	74068 KB	Output is correct
8	Correct	313 ms	77920 KB	Output is correct
9	Correct	299 ms	78640 KB	Output is correct
10	Correct	388 ms	73868 KB	Output is correct
11	Correct	395 ms	75132 KB	Output is correct
12	Correct	196 ms	72384 KB	Output is correct

Subtask #2

10.0 / 10.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	105 ms	65196 KB	Output is correct
2	Correct	106 ms	65144 KB	Output is correct
3	Correct	110 ms	65316 KB	Output is correct
4	Correct	106 ms	65292 KB	Output is correct
5	Correct	102 ms	65268 KB	Output is correct
6	Correct	109 ms	65208 KB	Output is correct
7	Correct	114 ms	65264 KB	Output is correct
8	Correct	110 ms	65332 KB	Output is correct
9	Correct	106 ms	65188 KB	Output is correct

Subtask #3

15.0 / 15.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	105 ms	65196 KB	Output is correct
2	Correct	106 ms	65144 KB	Output is correct
3	Correct	110 ms	65316 KB	Output is correct
4	Correct	106 ms	65292 KB	Output is correct
5	Correct	102 ms	65268 KB	Output is correct
6	Correct	109 ms	65208 KB	Output is correct
7	Correct	114 ms	65264 KB	Output is correct
8	Correct	110 ms	65332 KB	Output is correct
9	Correct	106 ms	65188 KB	Output is correct
10	Correct	116 ms	65220 KB	Output is correct
11	Correct	113 ms	65184 KB	Output is correct
12	Correct	111 ms	65296 KB	Output is correct
13	Correct	112 ms	65212 KB	Output is correct
14	Correct	110 ms	65316 KB	Output is correct
15	Correct	107 ms	65296 KB	Output is correct
16	Correct	106 ms	65344 KB	Output is correct
17	Correct	104 ms	65348 KB	Output is correct
18	Correct	103 ms	65252 KB	Output is correct
19	Correct	274 ms	66384 KB	Output is correct
20	Correct	205 ms	66768 KB	Output is correct
21	Correct	175 ms	66928 KB	Output is correct
22	Correct	187 ms	67148 KB	Output is correct
23	Correct	220 ms	66888 KB	Output is correct
24	Correct	228 ms	67032 KB	Output is correct
25	Correct	258 ms	66588 KB	Output is correct

Subtask #4

15.0 / 15.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	105 ms	65196 KB	Output is correct
2	Correct	106 ms	65144 KB	Output is correct
3	Correct	110 ms	65316 KB	Output is correct
4	Correct	106 ms	65292 KB	Output is correct
5	Correct	102 ms	65268 KB	Output is correct
6	Correct	109 ms	65208 KB	Output is correct
7	Correct	114 ms	65264 KB	Output is correct
8	Correct	110 ms	65332 KB	Output is correct
9	Correct	106 ms	65188 KB	Output is correct
10	Correct	105 ms	65184 KB	Output is correct
11	Correct	119 ms	65196 KB	Output is correct
12	Correct	115 ms	65296 KB	Output is correct
13	Correct	114 ms	65260 KB	Output is correct
14	Correct	118 ms	65316 KB	Output is correct
15	Correct	117 ms	65244 KB	Output is correct
16	Correct	120 ms	65260 KB	Output is correct
17	Correct	109 ms	65364 KB	Output is correct
18	Correct	113 ms	65256 KB	Output is correct
19	Correct	273 ms	72320 KB	Output is correct
20	Correct	260 ms	71064 KB	Output is correct
21	Correct	251 ms	71104 KB	Output is correct
22	Correct	332 ms	72688 KB	Output is correct
23	Correct	417 ms	75884 KB	Output is correct
24	Correct	370 ms	76276 KB	Output is correct
25	Correct	132 ms	66096 KB	Output is correct

Subtask #5

20.0 / 20.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	454 ms	71884 KB	Output is correct
2	Correct	425 ms	73512 KB	Output is correct
3	Correct	442 ms	72316 KB	Output is correct
4	Correct	283 ms	76592 KB	Output is correct
5	Correct	354 ms	71844 KB	Output is correct
6	Correct	593 ms	76444 KB	Output is correct
7	Correct	546 ms	76440 KB	Output is correct
8	Correct	504 ms	78796 KB	Output is correct
9	Correct	383 ms	75844 KB	Output is correct
10	Correct	575 ms	77480 KB	Output is correct
11	Correct	604 ms	77120 KB	Output is correct
12	Correct	564 ms	77296 KB	Output is correct

Subtask #6

30.0 / 30.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	103 ms	65236 KB	Output is correct
2	Correct	463 ms	71536 KB	Output is correct
3	Correct	411 ms	72256 KB	Output is correct
4	Correct	428 ms	72808 KB	Output is correct
5	Correct	467 ms	73420 KB	Output is correct
6	Correct	470 ms	74728 KB	Output is correct
7	Correct	451 ms	74068 KB	Output is correct
8	Correct	313 ms	77920 KB	Output is correct
9	Correct	299 ms	78640 KB	Output is correct
10	Correct	388 ms	73868 KB	Output is correct
11	Correct	395 ms	75132 KB	Output is correct
12	Correct	196 ms	72384 KB	Output is correct
13	Correct	105 ms	65196 KB	Output is correct
14	Correct	106 ms	65144 KB	Output is correct
15	Correct	110 ms	65316 KB	Output is correct
16	Correct	106 ms	65292 KB	Output is correct
17	Correct	102 ms	65268 KB	Output is correct
18	Correct	109 ms	65208 KB	Output is correct
19	Correct	114 ms	65264 KB	Output is correct
20	Correct	110 ms	65332 KB	Output is correct
21	Correct	106 ms	65188 KB	Output is correct
22	Correct	116 ms	65220 KB	Output is correct
23	Correct	113 ms	65184 KB	Output is correct
24	Correct	111 ms	65296 KB	Output is correct
25	Correct	112 ms	65212 KB	Output is correct
26	Correct	110 ms	65316 KB	Output is correct
27	Correct	107 ms	65296 KB	Output is correct
28	Correct	106 ms	65344 KB	Output is correct
29	Correct	104 ms	65348 KB	Output is correct
30	Correct	103 ms	65252 KB	Output is correct
31	Correct	274 ms	66384 KB	Output is correct
32	Correct	205 ms	66768 KB	Output is correct
33	Correct	175 ms	66928 KB	Output is correct
34	Correct	187 ms	67148 KB	Output is correct
35	Correct	220 ms	66888 KB	Output is correct
36	Correct	228 ms	67032 KB	Output is correct
37	Correct	258 ms	66588 KB	Output is correct
38	Correct	105 ms	65184 KB	Output is correct
39	Correct	119 ms	65196 KB	Output is correct
40	Correct	115 ms	65296 KB	Output is correct
41	Correct	114 ms	65260 KB	Output is correct
42	Correct	118 ms	65316 KB	Output is correct
43	Correct	117 ms	65244 KB	Output is correct
44	Correct	120 ms	65260 KB	Output is correct
45	Correct	109 ms	65364 KB	Output is correct
46	Correct	113 ms	65256 KB	Output is correct
47	Correct	273 ms	72320 KB	Output is correct
48	Correct	260 ms	71064 KB	Output is correct
49	Correct	251 ms	71104 KB	Output is correct
50	Correct	332 ms	72688 KB	Output is correct
51	Correct	417 ms	75884 KB	Output is correct
52	Correct	370 ms	76276 KB	Output is correct
53	Correct	132 ms	66096 KB	Output is correct
54	Correct	454 ms	71884 KB	Output is correct
55	Correct	425 ms	73512 KB	Output is correct
56	Correct	442 ms	72316 KB	Output is correct
57	Correct	283 ms	76592 KB	Output is correct
58	Correct	354 ms	71844 KB	Output is correct
59	Correct	593 ms	76444 KB	Output is correct
60	Correct	546 ms	76440 KB	Output is correct
61	Correct	504 ms	78796 KB	Output is correct
62	Correct	383 ms	75844 KB	Output is correct
63	Correct	575 ms	77480 KB	Output is correct
64	Correct	604 ms	77120 KB	Output is correct
65	Correct	564 ms	77296 KB	Output is correct
66	Correct	138 ms	65248 KB	Output is correct
67	Correct	481 ms	71708 KB	Output is correct
68	Correct	491 ms	72444 KB	Output is correct
69	Correct	482 ms	71548 KB	Output is correct
70	Correct	517 ms	72424 KB	Output is correct
71	Correct	553 ms	72676 KB	Output is correct
72	Correct	499 ms	73364 KB	Output is correct
73	Correct	370 ms	76828 KB	Output is correct
74	Correct	339 ms	79096 KB	Output is correct
75	Correct	442 ms	72208 KB	Output is correct
76	Correct	452 ms	73728 KB	Output is correct
77	Correct	211 ms	71968 KB	Output is correct
78	Correct	116 ms	65148 KB	Output is correct
79	Correct	135 ms	65220 KB	Output is correct
80	Correct	132 ms	65312 KB	Output is correct
81	Correct	118 ms	65292 KB	Output is correct
82	Correct	117 ms	65296 KB	Output is correct
83	Correct	124 ms	65284 KB	Output is correct
84	Correct	132 ms	65460 KB	Output is correct
85	Correct	126 ms	65188 KB	Output is correct
86	Correct	302 ms	66680 KB	Output is correct
87	Correct	248 ms	66876 KB	Output is correct
88	Correct	207 ms	66644 KB	Output is correct
89	Correct	199 ms	67060 KB	Output is correct
90	Correct	288 ms	67368 KB	Output is correct
91	Correct	226 ms	67148 KB	Output is correct
92	Correct	284 ms	66508 KB	Output is correct
93	Correct	308 ms	72164 KB	Output is correct
94	Correct	296 ms	71600 KB	Output is correct
95	Correct	319 ms	71872 KB	Output is correct
96	Correct	340 ms	72624 KB	Output is correct
97	Correct	462 ms	75888 KB	Output is correct
98	Correct	412 ms	75536 KB	Output is correct
99	Correct	150 ms	66188 KB	Output is correct
100	Correct	640 ms	76440 KB	Output is correct
101	Correct	612 ms	76780 KB	Output is correct
102	Correct	614 ms	77748 KB	Output is correct
103	Correct	659 ms	77736 KB	Output is correct
104	Correct	746 ms	76900 KB	Output is correct
105	Correct	638 ms	78184 KB	Output is correct
106	Correct	501 ms	72292 KB	Output is correct
107	Correct	490 ms	73720 KB	Output is correct
108	Correct	400 ms	73548 KB	Output is correct
109	Correct	400 ms	72812 KB	Output is correct
110	Correct	739 ms	76776 KB	Output is correct
111	Correct	727 ms	76404 KB	Output is correct