oj.uz

Submission #577670

# Submission time Handle Problem Language Result Execution time Memory
577670 2022-06-15T07:49:54 Z kingfran1907 Event Hopping (BOI22_events) C++14
50 / 100
 1500 ms 51944 KB 
#include <bits/stdc++.h>
#define X first
#define Y second

using namespace std;

const int maxn = 2e5+10;
const int inf = 0x3f3f3f3f;
const int logo = 20;
const int off = 1 << logo;
const int treesiz = off << 1;

int n, q;
pair<int, int> s[maxn];
vector< int > v;
int dp[30][maxn];
int mini[maxn];
int tour[logo][treesiz];

void update(int ind, int x, int val) {
	x += off;
	tour[ind][x] = val;
	
	x /= 2;
	while (x) tour[ind][x] = min(tour[ind][x * 2], tour[ind][x * 2 + 1]), x /= 2;
}

int query(int ind, int a, int b, int l, int r, int node) {
	if (l > b || r < a) return inf;
	if (l >= a && r <= b) return tour[ind][node];
	
	int mid = (l + r) / 2;
	return min(query(ind, a, b, l, mid, node * 2), query(ind, a, b, mid + 1, r, node * 2 + 1));
}

int main() {
	scanf("%d%d", &n, &q);
	for (int i = 0; i < n; i++) {
		int a, b;
		scanf("%d%d", &a, &b);
		s[i] = {a, b};
		v.push_back(a);
		v.push_back(b);
	}
	
	sort(v.begin(), v.end());
	v.resize(unique(v.begin(), v.end()) - v.begin());
	for (int i = 0; i < v.size(); i++) mini[i] = i;
	for (int i = 0; i < n; i++) {
		s[i].X = lower_bound(v.begin(), v.end(), s[i].X) - v.begin();
		s[i].Y = lower_bound(v.begin(), v.end(), s[i].Y) - v.begin();
		mini[s[i].Y] = min(mini[s[i].Y], s[i].X);
	}
	
	for (int i = 0; i < v.size(); i++) {
		dp[0][i] = mini[i];
		//printf("mini %d --> %d\n", i, mini[i]);
	}
	for (int i = 1; i < logo; i++) {
		for (int j = 0; j < v.size(); j++) update(i - 1, j, dp[i - 1][j]);
		for (int j = 0; j < v.size(); j++) {
			dp[i][j] = query(i - 1, dp[i - 1][j], j, 0, off - 1, 1);
		}
	}
	for (int i = 0; i < v.size(); i++) update(logo - 1, i, dp[logo - 1][i]);
	
	while (q--) {
		int a, b;
		scanf("%d%d", &a, &b); a--, b--;
		if (s[a].Y > s[b].Y) {
			printf("impossible\n");
			continue;
		}
		if (a == b) {
			printf("0\n");
			continue;
		}
		int ca = a, cb = b;
		
		int sol = inf;
		/*int dis = 0;
		b = s[b].Y;
		a = s[a].Y;
		for (int i = logo - 1; i >= 0; i--) {
			if (dp[i][b] > a) b = dp[i][b], dis += (1 << i);
			//printf("debug: %d %d\n", a, b);
		}
		if (mini[b] <= a)
			sol = min(sol, dis + 2);
		else {
			printf("impossible\n");
			continue;
		}*/
		
		int dis = 0;
		b = s[cb].Y;
		int l = s[cb].X;
		a = s[ca].Y;
		for (int i = logo - 1; i >= 0; i--) {
			int tren = query(i, l, b, 0, off - 1, 1);
			if (tren > a) l = tren, dis += (1 << i);
			//printf("debug: %d %d %d\n", a, l, b);
		}
		if (l <= a) sol = min(sol, dis + 1);
		if (query(0, l, b, 0, off - 1, 1) <= a) sol = min(dis + 2, sol);
		if (sol >= inf) printf("impossible\n");
		else printf("%d\n", sol);
	}
	return 0;
}

Compilation message

events.cpp: In function 'int main()':
events.cpp:48:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   48 |  for (int i = 0; i < v.size(); i++) mini[i] = i;
      |                  ~~^~~~~~~~~~
events.cpp:55:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   55 |  for (int i = 0; i < v.size(); i++) {
      |                  ~~^~~~~~~~~~
events.cpp:60:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   60 |   for (int j = 0; j < v.size(); j++) update(i - 1, j, dp[i - 1][j]);
      |                   ~~^~~~~~~~~~
events.cpp:61:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   61 |   for (int j = 0; j < v.size(); j++) {
      |                   ~~^~~~~~~~~~
events.cpp:65:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   65 |  for (int i = 0; i < v.size(); i++) update(logo - 1, i, dp[logo - 1][i]);
      |                  ~~^~~~~~~~~~
events.cpp:37:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   37 |  scanf("%d%d", &n, &q);
      |  ~~~~~^~~~~~~~~~~~~~~~
events.cpp:40:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   40 |   scanf("%d%d", &a, &b);
      |   ~~~~~^~~~~~~~~~~~~~~~
events.cpp:69:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   69 |   scanf("%d%d", &a, &b); a--, b--;
      |   ~~~~~^~~~~~~~~~~~~~~~

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1620 KB Output is correct
2 Correct 1162 ms 27764 KB Output is correct
3 Correct 1190 ms 27696 KB Output is correct
4 Correct 1179 ms 27760 KB Output is correct
5 Correct 1180 ms 30092 KB Output is correct
6 Correct 1208 ms 32184 KB Output is correct
7 Correct 1199 ms 33084 KB Output is correct
8 Correct 1213 ms 51860 KB Output is correct
9 Correct 1114 ms 51944 KB Output is correct
10 Correct 1046 ms 28180 KB Output is correct
11 Correct 1145 ms 37484 KB Output is correct
12 Correct 700 ms 28260 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 1620 KB Output is correct
2 Correct 1 ms 1568 KB Output is correct
3 Correct 9 ms 1704 KB Output is correct
4 Correct 6 ms 1688 KB Output is correct
5 Correct 7 ms 1748 KB Output is correct
6 Correct 5 ms 1748 KB Output is correct
7 Correct 14 ms 1940 KB Output is correct
8 Correct 13 ms 2024 KB Output is correct
9 Correct 1 ms 1620 KB Output is correct

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 1620 KB Output is correct
2 Correct 1 ms 1568 KB Output is correct
3 Correct 9 ms 1704 KB Output is correct
4 Correct 6 ms 1688 KB Output is correct
5 Correct 7 ms 1748 KB Output is correct
6 Correct 5 ms 1748 KB Output is correct
7 Correct 14 ms 1940 KB Output is correct
8 Correct 13 ms 2024 KB Output is correct
9 Correct 1 ms 1620 KB Output is correct
10 Correct 1 ms 1620 KB Output is correct
11 Correct 1 ms 1620 KB Output is correct
12 Correct 6 ms 1748 KB Output is correct
13 Correct 6 ms 1748 KB Output is correct
14 Correct 9 ms 1748 KB Output is correct
15 Correct 6 ms 1748 KB Output is correct
16 Correct 11 ms 2040 KB Output is correct
17 Correct 10 ms 2004 KB Output is correct
18 Correct 2 ms 1620 KB Output is correct
19 Correct 668 ms 3680 KB Output is correct
20 Correct 546 ms 3212 KB Output is correct
21 Correct 289 ms 3564 KB Output is correct
22 Correct 265 ms 3608 KB Output is correct
23 Correct 387 ms 4572 KB Output is correct
24 Correct 425 ms 4672 KB Output is correct
25 Correct 520 ms 4416 KB Output is correct

Subtask #4
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 1620 KB Output is correct
2 Correct 1 ms 1568 KB Output is correct
3 Correct 9 ms 1704 KB Output is correct
4 Correct 6 ms 1688 KB Output is correct
5 Correct 7 ms 1748 KB Output is correct
6 Correct 5 ms 1748 KB Output is correct
7 Correct 14 ms 1940 KB Output is correct
8 Correct 13 ms 2024 KB Output is correct
9 Correct 1 ms 1620 KB Output is correct
10 Correct 1 ms 1620 KB Output is correct
11 Correct 1 ms 1620 KB Output is correct
12 Correct 9 ms 1748 KB Output is correct
13 Correct 6 ms 1748 KB Output is correct
14 Correct 6 ms 1684 KB Output is correct
15 Correct 7 ms 1748 KB Output is correct
16 Correct 14 ms 2044 KB Output is correct
17 Correct 11 ms 2048 KB Output is correct
18 Correct 2 ms 1620 KB Output is correct
19 Correct 524 ms 27036 KB Output is correct
20 Correct 562 ms 27108 KB Output is correct
21 Correct 509 ms 27052 KB Output is correct
22 Correct 707 ms 35756 KB Output is correct
23 Correct 862 ms 50752 KB Output is correct
24 Correct 924 ms 50748 KB Output is correct
25 Correct 22 ms 3264 KB Output is correct

Subtask #5
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1191 ms 27664 KB Output is correct
2 Correct 1251 ms 27708 KB Output is correct
3 Correct 1248 ms 27804 KB Output is correct
4 Correct 1114 ms 51888 KB Output is correct
5 Correct 994 ms 27980 KB Output is correct
6 Correct 1459 ms 51528 KB Output is correct
7 Correct 1427 ms 51608 KB Output is correct
8 Execution timed out 1532 ms 51636 KB Time limit exceeded
9 Halted 0 ms 0 KB -

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1620 KB Output is correct
2 Correct 1162 ms 27764 KB Output is correct
3 Correct 1190 ms 27696 KB Output is correct
4 Correct 1179 ms 27760 KB Output is correct
5 Correct 1180 ms 30092 KB Output is correct
6 Correct 1208 ms 32184 KB Output is correct
7 Correct 1199 ms 33084 KB Output is correct
8 Correct 1213 ms 51860 KB Output is correct
9 Correct 1114 ms 51944 KB Output is correct
10 Correct 1046 ms 28180 KB Output is correct
11 Correct 1145 ms 37484 KB Output is correct
12 Correct 700 ms 28260 KB Output is correct
13 Correct 2 ms 1620 KB Output is correct
14 Correct 1 ms 1568 KB Output is correct
15 Correct 9 ms 1704 KB Output is correct
16 Correct 6 ms 1688 KB Output is correct
17 Correct 7 ms 1748 KB Output is correct
18 Correct 5 ms 1748 KB Output is correct
19 Correct 14 ms 1940 KB Output is correct
20 Correct 13 ms 2024 KB Output is correct
21 Correct 1 ms 1620 KB Output is correct
22 Correct 1 ms 1620 KB Output is correct
23 Correct 1 ms 1620 KB Output is correct
24 Correct 6 ms 1748 KB Output is correct
25 Correct 6 ms 1748 KB Output is correct
26 Correct 9 ms 1748 KB Output is correct
27 Correct 6 ms 1748 KB Output is correct
28 Correct 11 ms 2040 KB Output is correct
29 Correct 10 ms 2004 KB Output is correct
30 Correct 2 ms 1620 KB Output is correct
31 Correct 668 ms 3680 KB Output is correct
32 Correct 546 ms 3212 KB Output is correct
33 Correct 289 ms 3564 KB Output is correct
34 Correct 265 ms 3608 KB Output is correct
35 Correct 387 ms 4572 KB Output is correct
36 Correct 425 ms 4672 KB Output is correct
37 Correct 520 ms 4416 KB Output is correct
38 Correct 1 ms 1620 KB Output is correct
39 Correct 1 ms 1620 KB Output is correct
40 Correct 9 ms 1748 KB Output is correct
41 Correct 6 ms 1748 KB Output is correct
42 Correct 6 ms 1684 KB Output is correct
43 Correct 7 ms 1748 KB Output is correct
44 Correct 14 ms 2044 KB Output is correct
45 Correct 11 ms 2048 KB Output is correct
46 Correct 2 ms 1620 KB Output is correct
47 Correct 524 ms 27036 KB Output is correct
48 Correct 562 ms 27108 KB Output is correct
49 Correct 509 ms 27052 KB Output is correct
50 Correct 707 ms 35756 KB Output is correct
51 Correct 862 ms 50752 KB Output is correct
52 Correct 924 ms 50748 KB Output is correct
53 Correct 22 ms 3264 KB Output is correct
54 Correct 1191 ms 27664 KB Output is correct
55 Correct 1251 ms 27708 KB Output is correct
56 Correct 1248 ms 27804 KB Output is correct
57 Correct 1114 ms 51888 KB Output is correct
58 Correct 994 ms 27980 KB Output is correct
59 Correct 1459 ms 51528 KB Output is correct
60 Correct 1427 ms 51608 KB Output is correct
61 Execution timed out 1532 ms 51636 KB Time limit exceeded
62 Halted 0 ms 0 KB -