oj.uz

Submission #876927

# Submission time Handle Problem Language Result Execution time Memory
876927 2023-11-22T14:21:26 Z ninhtay Boat (APIO16_boat) C++14
100 / 100
 243 ms 8528 KB 
/*
	- Grid compression, at most 2*n points are important
	- dp[i][j] = number of ways with first i schools such that the number of boats sent <= pts[j]
	- To calculate dp[i][j], iterate through k<i
		- Use dp[k][j-1] to find how many ways need to be added if school k+1 is the first to send a number of boats > pts[j-1]
*/

#include <bits/stdc++.h>
using namespace std;

#define ll long long

const int mxN=500, M=1e9+7;
int n, a[mxN], b[mxN];
ll dp[mxN+1][2*mxN], c[2*mxN][mxN+1];
vector<int> pts;

inline ll modI(ll a, ll m) {
	return a<=1?a:(1-modI(m%a, a)*m)/a+m;
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	
	cin >> n;
	for(int i=0; i<n; ++i) {
		cin >> a[i] >> b[i], --a[i];
		pts.push_back(a[i]);
		pts.push_back(b[i]);
	}
	sort(pts.begin(), pts.end());
	pts.resize(unique(pts.begin(), pts.end())-pts.begin());
	for(int i=1; i<pts.size(); ++i) {
		c[i][1]=pts[i]-pts[i-1];
		for(int j=2; j<=n; ++j)
			c[i][j]=c[i][j-1]*(pts[i]-pts[i-1]+j-1)%M*modI(j, M)%M;
	}
	for(int i=0; i<pts.size(); ++i)
		dp[0][i]=1;
	for(int i=1; i<=n; ++i) {
		dp[i][0]=1;
		for(int j=1; j<pts.size(); ++j) {
			dp[i][j]=dp[i][j-1];
			for(int k=i, n2=0; k; --k) {
				if(pts[j]>a[k-1]&&pts[j]<=b[k-1]) {
					++n2;
					dp[i][j]+=dp[k-1][j-1]*c[j][n2]%M;
				}
			}
			dp[i][j]%=M;
		}
	}
	cout << dp[n][pts.size()-1]-1;
}

Compilation message

boat.cpp: In function 'int main()':
boat.cpp:34:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |  for(int i=1; i<pts.size(); ++i) {
      |               ~^~~~~~~~~~~
boat.cpp:39:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   39 |  for(int i=0; i<pts.size(); ++i)
      |               ~^~~~~~~~~~~
boat.cpp:43:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |   for(int j=1; j<pts.size(); ++j) {
      |                ~^~~~~~~~~~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 176 ms 8124 KB Output is correct
2 Correct 177 ms 8292 KB Output is correct
3 Correct 183 ms 8272 KB Output is correct
4 Correct 176 ms 8328 KB Output is correct
5 Correct 178 ms 8076 KB Output is correct
6 Correct 155 ms 8220 KB Output is correct
7 Correct 136 ms 8272 KB Output is correct
8 Correct 140 ms 8276 KB Output is correct
9 Correct 143 ms 8168 KB Output is correct
10 Correct 141 ms 8084 KB Output is correct
11 Correct 139 ms 8276 KB Output is correct
12 Correct 146 ms 8076 KB Output is correct
13 Correct 142 ms 8276 KB Output is correct
14 Correct 142 ms 8088 KB Output is correct
15 Correct 146 ms 8080 KB Output is correct
16 Correct 38 ms 7800 KB Output is correct
17 Correct 41 ms 7764 KB Output is correct
18 Correct 40 ms 7760 KB Output is correct
19 Correct 42 ms 7764 KB Output is correct
20 Correct 42 ms 7760 KB Output is correct

Subtask #2
22.0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 176 ms 8124 KB Output is correct
2 Correct 177 ms 8292 KB Output is correct
3 Correct 183 ms 8272 KB Output is correct
4 Correct 176 ms 8328 KB Output is correct
5 Correct 178 ms 8076 KB Output is correct
6 Correct 155 ms 8220 KB Output is correct
7 Correct 136 ms 8272 KB Output is correct
8 Correct 140 ms 8276 KB Output is correct
9 Correct 143 ms 8168 KB Output is correct
10 Correct 141 ms 8084 KB Output is correct
11 Correct 139 ms 8276 KB Output is correct
12 Correct 146 ms 8076 KB Output is correct
13 Correct 142 ms 8276 KB Output is correct
14 Correct 142 ms 8088 KB Output is correct
15 Correct 146 ms 8080 KB Output is correct
16 Correct 38 ms 7800 KB Output is correct
17 Correct 41 ms 7764 KB Output is correct
18 Correct 40 ms 7760 KB Output is correct
19 Correct 42 ms 7764 KB Output is correct
20 Correct 42 ms 7760 KB Output is correct
21 Correct 206 ms 8276 KB Output is correct
22 Correct 197 ms 8120 KB Output is correct
23 Correct 199 ms 8068 KB Output is correct
24 Correct 196 ms 8272 KB Output is correct
25 Correct 201 ms 8072 KB Output is correct
26 Correct 197 ms 8072 KB Output is correct
27 Correct 203 ms 8264 KB Output is correct
28 Correct 195 ms 8188 KB Output is correct
29 Correct 199 ms 8068 KB Output is correct
30 Correct 146 ms 8076 KB Output is correct
31 Correct 138 ms 8276 KB Output is correct
32 Correct 144 ms 8272 KB Output is correct
33 Correct 137 ms 8272 KB Output is correct
34 Correct 138 ms 8084 KB Output is correct
35 Correct 182 ms 8264 KB Output is correct
36 Correct 190 ms 8528 KB Output is correct
37 Correct 179 ms 8272 KB Output is correct
38 Correct 181 ms 8276 KB Output is correct

Subtask #3
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 6744 KB Output is correct
2 Correct 4 ms 6748 KB Output is correct
3 Correct 3 ms 6748 KB Output is correct
4 Correct 5 ms 6748 KB Output is correct
5 Correct 3 ms 6792 KB Output is correct
6 Correct 4 ms 6748 KB Output is correct
7 Correct 4 ms 6748 KB Output is correct
8 Correct 4 ms 6748 KB Output is correct
9 Correct 4 ms 6748 KB Output is correct
10 Correct 4 ms 6748 KB Output is correct
11 Correct 3 ms 6748 KB Output is correct
12 Correct 4 ms 6748 KB Output is correct
13 Correct 4 ms 6748 KB Output is correct
14 Correct 4 ms 6748 KB Output is correct
15 Correct 4 ms 6748 KB Output is correct
16 Correct 2 ms 6748 KB Output is correct
17 Correct 3 ms 6748 KB Output is correct
18 Correct 2 ms 6748 KB Output is correct
19 Correct 3 ms 6748 KB Output is correct
20 Correct 3 ms 6748 KB Output is correct

Subtask #4
42.0 / 42.0

# Verdict Execution time Memory Grader output
1 Correct 176 ms 8124 KB Output is correct
2 Correct 177 ms 8292 KB Output is correct
3 Correct 183 ms 8272 KB Output is correct
4 Correct 176 ms 8328 KB Output is correct
5 Correct 178 ms 8076 KB Output is correct
6 Correct 155 ms 8220 KB Output is correct
7 Correct 136 ms 8272 KB Output is correct
8 Correct 140 ms 8276 KB Output is correct
9 Correct 143 ms 8168 KB Output is correct
10 Correct 141 ms 8084 KB Output is correct
11 Correct 139 ms 8276 KB Output is correct
12 Correct 146 ms 8076 KB Output is correct
13 Correct 142 ms 8276 KB Output is correct
14 Correct 142 ms 8088 KB Output is correct
15 Correct 146 ms 8080 KB Output is correct
16 Correct 38 ms 7800 KB Output is correct
17 Correct 41 ms 7764 KB Output is correct
18 Correct 40 ms 7760 KB Output is correct
19 Correct 42 ms 7764 KB Output is correct
20 Correct 42 ms 7760 KB Output is correct
21 Correct 206 ms 8276 KB Output is correct
22 Correct 197 ms 8120 KB Output is correct
23 Correct 199 ms 8068 KB Output is correct
24 Correct 196 ms 8272 KB Output is correct
25 Correct 201 ms 8072 KB Output is correct
26 Correct 197 ms 8072 KB Output is correct
27 Correct 203 ms 8264 KB Output is correct
28 Correct 195 ms 8188 KB Output is correct
29 Correct 199 ms 8068 KB Output is correct
30 Correct 146 ms 8076 KB Output is correct
31 Correct 138 ms 8276 KB Output is correct
32 Correct 144 ms 8272 KB Output is correct
33 Correct 137 ms 8272 KB Output is correct
34 Correct 138 ms 8084 KB Output is correct
35 Correct 182 ms 8264 KB Output is correct
36 Correct 190 ms 8528 KB Output is correct
37 Correct 179 ms 8272 KB Output is correct
38 Correct 181 ms 8276 KB Output is correct
39 Correct 4 ms 6744 KB Output is correct
40 Correct 4 ms 6748 KB Output is correct
41 Correct 3 ms 6748 KB Output is correct
42 Correct 5 ms 6748 KB Output is correct
43 Correct 3 ms 6792 KB Output is correct
44 Correct 4 ms 6748 KB Output is correct
45 Correct 4 ms 6748 KB Output is correct
46 Correct 4 ms 6748 KB Output is correct
47 Correct 4 ms 6748 KB Output is correct
48 Correct 4 ms 6748 KB Output is correct
49 Correct 3 ms 6748 KB Output is correct
50 Correct 4 ms 6748 KB Output is correct
51 Correct 4 ms 6748 KB Output is correct
52 Correct 4 ms 6748 KB Output is correct
53 Correct 4 ms 6748 KB Output is correct
54 Correct 2 ms 6748 KB Output is correct
55 Correct 3 ms 6748 KB Output is correct
56 Correct 2 ms 6748 KB Output is correct
57 Correct 3 ms 6748 KB Output is correct
58 Correct 3 ms 6748 KB Output is correct
59 Correct 214 ms 8300 KB Output is correct
60 Correct 214 ms 8272 KB Output is correct
61 Correct 219 ms 8128 KB Output is correct
62 Correct 214 ms 8248 KB Output is correct
63 Correct 214 ms 8272 KB Output is correct
64 Correct 225 ms 8272 KB Output is correct
65 Correct 243 ms 8276 KB Output is correct
66 Correct 222 ms 8276 KB Output is correct
67 Correct 226 ms 8272 KB Output is correct
68 Correct 216 ms 8132 KB Output is correct
69 Correct 203 ms 8076 KB Output is correct
70 Correct 202 ms 8256 KB Output is correct
71 Correct 204 ms 8072 KB Output is correct
72 Correct 209 ms 8052 KB Output is correct
73 Correct 208 ms 8096 KB Output is correct
74 Correct 50 ms 7728 KB Output is correct
75 Correct 53 ms 7764 KB Output is correct
76 Correct 52 ms 7832 KB Output is correct
77 Correct 51 ms 7708 KB Output is correct
78 Correct 52 ms 8016 KB Output is correct