Submission #551919

# Submission time Handle Problem Language Result Execution time Memory
551919 2022-04-21T22:13:31 Z nafis_shifat Boat (APIO16_boat) C++17
100 / 100
1454 ms 36028 KB
#include<bits/stdc++.h>
#define ll long long
#define pii pair<int,int>
using namespace std;
const int mxn=1500+5;
const int inf=1e9;
const ll mod = 1e9 + 7;
ll bigmod(ll a, ll b) {
	if(b == 0) return 1;
	int mid = b / 2;

	ll res = bigmod(a, mid);
	res = res * res % mod;
	if(b % 2 == 1) return a * res % mod;
	return res;
}

ll last[mxn][mxn] = {};
ll dp[mxn][mxn] = {};
ll sum[mxn][mxn] = {};

ll fact[mxn], inv[mxn];

ll pre[mxn][mxn] = {};

ll ncr(ll n, ll r) {
	if(r > n) return 0;
	ll res = fact[n];
	res = res * inv[r] % mod;
	res = res * inv[n - r] % mod;
	return res;
}
int main() {
	fact[0] = 1;
	inv[0] = 1;

	for(int i = 1; i < mxn; i++) {
		fact[i] = fact[i - 1] * i % mod;
		inv[i] = bigmod(fact[i], mod - 2) % mod;
	}

	int n;
	cin >> n;
	int a[n + 1], b[n + 1];
	int l[n + 1] = {}, r[n + 1] = {};
	vector<int> v;
	v.push_back(0);
	for(int i = 1; i <= n; i++) {
		cin >> a[i] >> b[i];
		v.push_back(a[i]);
		v.push_back(a[i] - 1);
		v.push_back(b[i]);

	}
	sort(v.begin(), v.end());
	v.erase(unique(v.begin(), v.end()), v.end());

	int len[v.size() + 2];
	for(int i = 1; i < v.size(); i++) len[i] = v[i] - v[i - 1];


	for(int i = 1; i < v.size(); i++) {
		
		for(int j = 1; j <= n; j++) {
			ll mul = 1;
			ll tot = 0;
			ll mul2 = 1;

			for(int k = 1; k <= min(j + 1, len[i]); k++) {

				mul = mul * (len[i] - k + 1) % mod;
				ll v1 = mul * inv[k] % mod;

				ll v2 = mul2 * inv[k - 1] % mod;

				// cout<<i<<" "<<j<<" "<<k<<endl;
				// assert(ncr(j - 1, k - 1) == v2);
				pre[i][j] += v2 * v1 % mod;

				mul2 = mul2 * (j - k) % mod;


			}


			pre[i][j] %= mod;
		}
	}



	for(int i = 1; i <= n; i++) {
		l[i] = lower_bound(v.begin(), v.end(), a[i]) - v.begin();
		r[i] = lower_bound(v.begin(), v.end(), b[i]) - v.begin();
	}

	dp[0][0] = 1;
	for(int i = 0; i < v.size(); i++) sum[i][0] = 1;

	ll ans = 0;

    for(int p = 1; p <= n; p++) {
    	for(int i = l[p]; i <= r[p]; i++) {
    		ll tot = len[i];
    		ll found = 1;

    		for(int j = p - 1; j >= 0; j--) {


    			dp[i][j] = sum[i - 1][j] * pre[i][found] % mod;
    			sum[i][p] = (sum[i][p] + dp[i][j]) % mod;

    			if(l[j] <= i && i <= r[j]) found++;




    		}
    	}

    	for(int i = l[p]; i < v.size(); i++) sum[i][p] = (sum[i][p] + sum[i - 1][p]) % mod;

    	ans += sum[v.size() - 1][p];

  

    }



    cout<<ans % mod<<endl;


	
}

Compilation message

boat.cpp: In function 'int main()':
boat.cpp:59:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   59 |  for(int i = 1; i < v.size(); i++) len[i] = v[i] - v[i - 1];
      |                 ~~^~~~~~~~~~
boat.cpp:62:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   62 |  for(int i = 1; i < v.size(); i++) {
      |                 ~~^~~~~~~~~~
boat.cpp:66:7: warning: unused variable 'tot' [-Wunused-variable]
   66 |    ll tot = 0;
      |       ^~~
boat.cpp:98:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   98 |  for(int i = 0; i < v.size(); i++) sum[i][0] = 1;
      |                 ~~^~~~~~~~~~
boat.cpp:104:10: warning: unused variable 'tot' [-Wunused-variable]
  104 |       ll tot = len[i];
      |          ^~~
boat.cpp:121:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  121 |      for(int i = l[p]; i < v.size(); i++) sum[i][p] = (sum[i][p] + sum[i - 1][p]) % mod;
      |                        ~~^~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 522 ms 19176 KB Output is correct
2 Correct 516 ms 19160 KB Output is correct
3 Correct 526 ms 19156 KB Output is correct
4 Correct 515 ms 19168 KB Output is correct
5 Correct 510 ms 19148 KB Output is correct
6 Correct 530 ms 18080 KB Output is correct
7 Correct 528 ms 17800 KB Output is correct
8 Correct 518 ms 18372 KB Output is correct
9 Correct 518 ms 18344 KB Output is correct
10 Correct 520 ms 18488 KB Output is correct
11 Correct 520 ms 18284 KB Output is correct
12 Correct 523 ms 19220 KB Output is correct
13 Correct 519 ms 18476 KB Output is correct
14 Correct 522 ms 18004 KB Output is correct
15 Correct 524 ms 18632 KB Output is correct
16 Correct 95 ms 3800 KB Output is correct
17 Correct 102 ms 3912 KB Output is correct
18 Correct 95 ms 3756 KB Output is correct
19 Correct 103 ms 4008 KB Output is correct
20 Correct 98 ms 3880 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 522 ms 19176 KB Output is correct
2 Correct 516 ms 19160 KB Output is correct
3 Correct 526 ms 19156 KB Output is correct
4 Correct 515 ms 19168 KB Output is correct
5 Correct 510 ms 19148 KB Output is correct
6 Correct 530 ms 18080 KB Output is correct
7 Correct 528 ms 17800 KB Output is correct
8 Correct 518 ms 18372 KB Output is correct
9 Correct 518 ms 18344 KB Output is correct
10 Correct 520 ms 18488 KB Output is correct
11 Correct 520 ms 18284 KB Output is correct
12 Correct 523 ms 19220 KB Output is correct
13 Correct 519 ms 18476 KB Output is correct
14 Correct 522 ms 18004 KB Output is correct
15 Correct 524 ms 18632 KB Output is correct
16 Correct 95 ms 3800 KB Output is correct
17 Correct 102 ms 3912 KB Output is correct
18 Correct 95 ms 3756 KB Output is correct
19 Correct 103 ms 4008 KB Output is correct
20 Correct 98 ms 3880 KB Output is correct
21 Correct 335 ms 31304 KB Output is correct
22 Correct 335 ms 31592 KB Output is correct
23 Correct 302 ms 30900 KB Output is correct
24 Correct 333 ms 31300 KB Output is correct
25 Correct 319 ms 30668 KB Output is correct
26 Correct 376 ms 27684 KB Output is correct
27 Correct 368 ms 28624 KB Output is correct
28 Correct 381 ms 28872 KB Output is correct
29 Correct 371 ms 28732 KB Output is correct
30 Correct 499 ms 31272 KB Output is correct
31 Correct 518 ms 30516 KB Output is correct
32 Correct 520 ms 30888 KB Output is correct
33 Correct 509 ms 30824 KB Output is correct
34 Correct 505 ms 30564 KB Output is correct
35 Correct 506 ms 22400 KB Output is correct
36 Correct 488 ms 22316 KB Output is correct
37 Correct 509 ms 22476 KB Output is correct
38 Correct 493 ms 22436 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 14 ms 4640 KB Output is correct
2 Correct 14 ms 4568 KB Output is correct
3 Correct 13 ms 4596 KB Output is correct
4 Correct 14 ms 4580 KB Output is correct
5 Correct 15 ms 4564 KB Output is correct
6 Correct 14 ms 4488 KB Output is correct
7 Correct 15 ms 4552 KB Output is correct
8 Correct 17 ms 4520 KB Output is correct
9 Correct 15 ms 4512 KB Output is correct
10 Correct 14 ms 4568 KB Output is correct
11 Correct 13 ms 4572 KB Output is correct
12 Correct 13 ms 4564 KB Output is correct
13 Correct 13 ms 4436 KB Output is correct
14 Correct 14 ms 4564 KB Output is correct
15 Correct 14 ms 4564 KB Output is correct
16 Correct 7 ms 2388 KB Output is correct
17 Correct 6 ms 2388 KB Output is correct
18 Correct 8 ms 2396 KB Output is correct
19 Correct 7 ms 2348 KB Output is correct
20 Correct 7 ms 2388 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 522 ms 19176 KB Output is correct
2 Correct 516 ms 19160 KB Output is correct
3 Correct 526 ms 19156 KB Output is correct
4 Correct 515 ms 19168 KB Output is correct
5 Correct 510 ms 19148 KB Output is correct
6 Correct 530 ms 18080 KB Output is correct
7 Correct 528 ms 17800 KB Output is correct
8 Correct 518 ms 18372 KB Output is correct
9 Correct 518 ms 18344 KB Output is correct
10 Correct 520 ms 18488 KB Output is correct
11 Correct 520 ms 18284 KB Output is correct
12 Correct 523 ms 19220 KB Output is correct
13 Correct 519 ms 18476 KB Output is correct
14 Correct 522 ms 18004 KB Output is correct
15 Correct 524 ms 18632 KB Output is correct
16 Correct 95 ms 3800 KB Output is correct
17 Correct 102 ms 3912 KB Output is correct
18 Correct 95 ms 3756 KB Output is correct
19 Correct 103 ms 4008 KB Output is correct
20 Correct 98 ms 3880 KB Output is correct
21 Correct 335 ms 31304 KB Output is correct
22 Correct 335 ms 31592 KB Output is correct
23 Correct 302 ms 30900 KB Output is correct
24 Correct 333 ms 31300 KB Output is correct
25 Correct 319 ms 30668 KB Output is correct
26 Correct 376 ms 27684 KB Output is correct
27 Correct 368 ms 28624 KB Output is correct
28 Correct 381 ms 28872 KB Output is correct
29 Correct 371 ms 28732 KB Output is correct
30 Correct 499 ms 31272 KB Output is correct
31 Correct 518 ms 30516 KB Output is correct
32 Correct 520 ms 30888 KB Output is correct
33 Correct 509 ms 30824 KB Output is correct
34 Correct 505 ms 30564 KB Output is correct
35 Correct 506 ms 22400 KB Output is correct
36 Correct 488 ms 22316 KB Output is correct
37 Correct 509 ms 22476 KB Output is correct
38 Correct 493 ms 22436 KB Output is correct
39 Correct 14 ms 4640 KB Output is correct
40 Correct 14 ms 4568 KB Output is correct
41 Correct 13 ms 4596 KB Output is correct
42 Correct 14 ms 4580 KB Output is correct
43 Correct 15 ms 4564 KB Output is correct
44 Correct 14 ms 4488 KB Output is correct
45 Correct 15 ms 4552 KB Output is correct
46 Correct 17 ms 4520 KB Output is correct
47 Correct 15 ms 4512 KB Output is correct
48 Correct 14 ms 4568 KB Output is correct
49 Correct 13 ms 4572 KB Output is correct
50 Correct 13 ms 4564 KB Output is correct
51 Correct 13 ms 4436 KB Output is correct
52 Correct 14 ms 4564 KB Output is correct
53 Correct 14 ms 4564 KB Output is correct
54 Correct 7 ms 2388 KB Output is correct
55 Correct 6 ms 2388 KB Output is correct
56 Correct 8 ms 2396 KB Output is correct
57 Correct 7 ms 2348 KB Output is correct
58 Correct 7 ms 2388 KB Output is correct
59 Correct 1359 ms 36028 KB Output is correct
60 Correct 1336 ms 35788 KB Output is correct
61 Correct 1340 ms 35872 KB Output is correct
62 Correct 1373 ms 35728 KB Output is correct
63 Correct 1351 ms 35900 KB Output is correct
64 Correct 1454 ms 34528 KB Output is correct
65 Correct 1434 ms 33612 KB Output is correct
66 Correct 1441 ms 34788 KB Output is correct
67 Correct 1432 ms 34172 KB Output is correct
68 Correct 1423 ms 35244 KB Output is correct
69 Correct 1249 ms 33840 KB Output is correct
70 Correct 1248 ms 34664 KB Output is correct
71 Correct 1231 ms 33620 KB Output is correct
72 Correct 1247 ms 34020 KB Output is correct
73 Correct 1253 ms 34236 KB Output is correct
74 Correct 148 ms 4812 KB Output is correct
75 Correct 147 ms 4904 KB Output is correct
76 Correct 151 ms 4964 KB Output is correct
77 Correct 150 ms 4856 KB Output is correct
78 Correct 148 ms 4804 KB Output is correct