oj.uz

Submission #259048

# Submission time Handle Problem Language Result Execution time Memory
259048 2020-08-07T05:08:49 Z ChrisT Boat (APIO16_boat) C++17
100 / 100
 1992 ms 11640 KB 
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int,int>;
const int MN = 505, LOG = 18, MOD = 1e9 + 7;
int dp[MN][MN<<1],pre[MN<<1][MN][2],a[MN],b[MN];
int ch[MN][MN], ch2[MN<<1][MN][2], iv[MN<<1];
int inv (int base) {
	int res = 1, exp = MOD - 2;
	while (exp) {
		if (exp&1) res = (ll)res * base % MOD;
		base = (ll)base * base % MOD;
		exp>>=1;
	}
	return res;
}
int choose (int n, int k) {
	assert(n >= 0 && k >= 0);
	int res = 1;
	for (int i = n; i > n-k; i--) res = (ll)res * i % MOD;
	for (int i = 2; i <= k; i++) res = (ll)res * iv[i] % MOD;
	return res;
}
int calc (int j, int x, bool ree) {
	int ret = ch2[j][x-ree][ree];
	for (int zeros = 1; zeros <= x-2; zeros++) ret = (ret + (ll)ch2[j][x-zeros-ree][ree] * ch[x-2][zeros]) % MOD;
	return ret;
}
int main () {
	int n;
	scanf ("%d",&n);
	for (int i = 0; i <= n*2; i++) iv[i] = inv(i);
	for (int i = 0; i <= n; i++) for (int j = 0; j <= i; j++) ch[i][j] = choose(i,j);
	vector<int> xs = {-1};
	for (int i = 1; i <= n; i++) {
		scanf ("%d %d",&a[i],&b[i]);
		xs.push_back(a[i]); xs.push_back(b[i]);
	}
	sort(xs.begin(),xs.end()); xs.erase(unique(xs.begin(),xs.end()),xs.end());
	int m = xs.size() - 1;
	for (int j = 1; j <= m; j++) {
		ch2[j][0][0] = ch2[j][0][1] = 1;
		for (int i = 1; i <= n; i++) {
			ch2[j][i][0] = (ll)ch2[j][i-1][0] * (xs[j]-xs[j-1]-i+1) % MOD * inv(i) % MOD;
			ch2[j][i][1] = (ll)ch2[j][i-1][1] * (xs[j]-xs[j-1]-i) % MOD * inv(i) % MOD;
		}
	}
	for (int j = 1; j <= m; j++) {
		for (int i = 1; i <= n; i++) {
			pre[j][i][0] = calc(j,i,0);
			pre[j][i][1] = calc(j,i,1);
		}
	}
	for (int j = 0; j <= m; j++) dp[0][j] = 1;
	for (int i = 1; i <= n; i++) {
		//printf ("i %d\n",i);
		for (int j = 0; j <= m; j++){
			if (j) dp[i][j] = (dp[i][j] + dp[i][j-1]) % MOD;
			if (xs[j] < a[i] || (j&&b[i] <= xs[j-1])) continue;
			bool ree = a[i]==xs[j]; int cnt = 0;
			for (int k = i; k >= 1; k--) { //everything before k was <= xs[j-1]
				if (a[k] > xs[j] || b[k] <= xs[j-1] || (k!=i&&a[k]==xs[j])) continue;
				++cnt;
				dp[i][j] = (dp[i][j] + (ll)dp[k-1][j-1] * pre[j][cnt][ree]) % MOD;
			}
		}
		for (int j = 0; j <= m; j++) {
			dp[i][j] = (dp[i][j] + dp[i-1][j]) % MOD;
			//printf ("dp[%d][%d] = %d\n",i,j,dp[i][j]);
		}
	}
	printf ("%d\n",(dp[n][m] + MOD - 1) % MOD);
	return 0;
}

Compilation message

boat.cpp: In function 'int main()':
boat.cpp:31:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf ("%d",&n);
  ~~~~~~^~~~~~~~~
boat.cpp:36:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf ("%d %d",&a[i],&b[i]);
   ~~~~~~^~~~~~~~~~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 938 ms 7416 KB Output is correct
2 Correct 948 ms 7476 KB Output is correct
3 Correct 937 ms 7416 KB Output is correct
4 Correct 940 ms 7544 KB Output is correct
5 Correct 946 ms 7324 KB Output is correct
6 Correct 937 ms 7468 KB Output is correct
7 Correct 939 ms 7216 KB Output is correct
8 Correct 937 ms 7288 KB Output is correct
9 Correct 937 ms 7412 KB Output is correct
10 Correct 936 ms 7260 KB Output is correct
11 Correct 933 ms 7288 KB Output is correct
12 Correct 938 ms 7288 KB Output is correct
13 Correct 938 ms 7416 KB Output is correct
14 Correct 941 ms 7288 KB Output is correct
15 Correct 941 ms 7288 KB Output is correct
16 Correct 363 ms 4040 KB Output is correct
17 Correct 373 ms 4088 KB Output is correct
18 Correct 365 ms 4088 KB Output is correct
19 Correct 371 ms 4188 KB Output is correct
20 Correct 365 ms 4088 KB Output is correct

Subtask #2
22.0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 938 ms 7416 KB Output is correct
2 Correct 948 ms 7476 KB Output is correct
3 Correct 937 ms 7416 KB Output is correct
4 Correct 940 ms 7544 KB Output is correct
5 Correct 946 ms 7324 KB Output is correct
6 Correct 937 ms 7468 KB Output is correct
7 Correct 939 ms 7216 KB Output is correct
8 Correct 937 ms 7288 KB Output is correct
9 Correct 937 ms 7412 KB Output is correct
10 Correct 936 ms 7260 KB Output is correct
11 Correct 933 ms 7288 KB Output is correct
12 Correct 938 ms 7288 KB Output is correct
13 Correct 938 ms 7416 KB Output is correct
14 Correct 941 ms 7288 KB Output is correct
15 Correct 941 ms 7288 KB Output is correct
16 Correct 363 ms 4040 KB Output is correct
17 Correct 373 ms 4088 KB Output is correct
18 Correct 365 ms 4088 KB Output is correct
19 Correct 371 ms 4188 KB Output is correct
20 Correct 365 ms 4088 KB Output is correct
21 Correct 1672 ms 10548 KB Output is correct
22 Correct 1665 ms 10720 KB Output is correct
23 Correct 1638 ms 10588 KB Output is correct
24 Correct 1653 ms 10604 KB Output is correct
25 Correct 1644 ms 10360 KB Output is correct
26 Correct 1781 ms 10232 KB Output is correct
27 Correct 1807 ms 10360 KB Output is correct
28 Correct 1784 ms 10328 KB Output is correct
29 Correct 1785 ms 10336 KB Output is correct
30 Correct 1584 ms 11000 KB Output is correct
31 Correct 1574 ms 10840 KB Output is correct
32 Correct 1581 ms 10820 KB Output is correct
33 Correct 1611 ms 11000 KB Output is correct
34 Correct 1558 ms 10912 KB Output is correct
35 Correct 939 ms 7388 KB Output is correct
36 Correct 939 ms 7416 KB Output is correct
37 Correct 942 ms 7416 KB Output is correct
38 Correct 941 ms 7312 KB Output is correct

Subtask #3
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 23 ms 2552 KB Output is correct
2 Correct 21 ms 2560 KB Output is correct
3 Correct 22 ms 2552 KB Output is correct
4 Correct 25 ms 2556 KB Output is correct
5 Correct 22 ms 2560 KB Output is correct
6 Correct 24 ms 2560 KB Output is correct
7 Correct 23 ms 2552 KB Output is correct
8 Correct 23 ms 2560 KB Output is correct
9 Correct 23 ms 2560 KB Output is correct
10 Correct 23 ms 2560 KB Output is correct
11 Correct 22 ms 2560 KB Output is correct
12 Correct 21 ms 2560 KB Output is correct
13 Correct 22 ms 2536 KB Output is correct
14 Correct 21 ms 2560 KB Output is correct
15 Correct 21 ms 2552 KB Output is correct
16 Correct 11 ms 1664 KB Output is correct
17 Correct 11 ms 1664 KB Output is correct
18 Correct 11 ms 1664 KB Output is correct
19 Correct 11 ms 1664 KB Output is correct
20 Correct 11 ms 1664 KB Output is correct

Subtask #4
42.0 / 42.0

# Verdict Execution time Memory Grader output
1 Correct 938 ms 7416 KB Output is correct
2 Correct 948 ms 7476 KB Output is correct
3 Correct 937 ms 7416 KB Output is correct
4 Correct 940 ms 7544 KB Output is correct
5 Correct 946 ms 7324 KB Output is correct
6 Correct 937 ms 7468 KB Output is correct
7 Correct 939 ms 7216 KB Output is correct
8 Correct 937 ms 7288 KB Output is correct
9 Correct 937 ms 7412 KB Output is correct
10 Correct 936 ms 7260 KB Output is correct
11 Correct 933 ms 7288 KB Output is correct
12 Correct 938 ms 7288 KB Output is correct
13 Correct 938 ms 7416 KB Output is correct
14 Correct 941 ms 7288 KB Output is correct
15 Correct 941 ms 7288 KB Output is correct
16 Correct 363 ms 4040 KB Output is correct
17 Correct 373 ms 4088 KB Output is correct
18 Correct 365 ms 4088 KB Output is correct
19 Correct 371 ms 4188 KB Output is correct
20 Correct 365 ms 4088 KB Output is correct
21 Correct 1672 ms 10548 KB Output is correct
22 Correct 1665 ms 10720 KB Output is correct
23 Correct 1638 ms 10588 KB Output is correct
24 Correct 1653 ms 10604 KB Output is correct
25 Correct 1644 ms 10360 KB Output is correct
26 Correct 1781 ms 10232 KB Output is correct
27 Correct 1807 ms 10360 KB Output is correct
28 Correct 1784 ms 10328 KB Output is correct
29 Correct 1785 ms 10336 KB Output is correct
30 Correct 1584 ms 11000 KB Output is correct
31 Correct 1574 ms 10840 KB Output is correct
32 Correct 1581 ms 10820 KB Output is correct
33 Correct 1611 ms 11000 KB Output is correct
34 Correct 1558 ms 10912 KB Output is correct
35 Correct 939 ms 7388 KB Output is correct
36 Correct 939 ms 7416 KB Output is correct
37 Correct 942 ms 7416 KB Output is correct
38 Correct 941 ms 7312 KB Output is correct
39 Correct 23 ms 2552 KB Output is correct
40 Correct 21 ms 2560 KB Output is correct
41 Correct 22 ms 2552 KB Output is correct
42 Correct 25 ms 2556 KB Output is correct
43 Correct 22 ms 2560 KB Output is correct
44 Correct 24 ms 2560 KB Output is correct
45 Correct 23 ms 2552 KB Output is correct
46 Correct 23 ms 2560 KB Output is correct
47 Correct 23 ms 2560 KB Output is correct
48 Correct 23 ms 2560 KB Output is correct
49 Correct 22 ms 2560 KB Output is correct
50 Correct 21 ms 2560 KB Output is correct
51 Correct 22 ms 2536 KB Output is correct
52 Correct 21 ms 2560 KB Output is correct
53 Correct 21 ms 2552 KB Output is correct
54 Correct 11 ms 1664 KB Output is correct
55 Correct 11 ms 1664 KB Output is correct
56 Correct 11 ms 1664 KB Output is correct
57 Correct 11 ms 1664 KB Output is correct
58 Correct 11 ms 1664 KB Output is correct
59 Correct 1811 ms 11512 KB Output is correct
60 Correct 1787 ms 11276 KB Output is correct
61 Correct 1777 ms 11384 KB Output is correct
62 Correct 1803 ms 11376 KB Output is correct
63 Correct 1804 ms 11368 KB Output is correct
64 Correct 1991 ms 11384 KB Output is correct
65 Correct 1988 ms 11556 KB Output is correct
66 Correct 1989 ms 11216 KB Output is correct
67 Correct 1992 ms 11364 KB Output is correct
68 Correct 1985 ms 11316 KB Output is correct
69 Correct 1768 ms 11408 KB Output is correct
70 Correct 1767 ms 11384 KB Output is correct
71 Correct 1764 ms 11516 KB Output is correct
72 Correct 1776 ms 11384 KB Output is correct
73 Correct 1781 ms 11640 KB Output is correct
74 Correct 403 ms 4088 KB Output is correct
75 Correct 398 ms 4344 KB Output is correct
76 Correct 401 ms 4088 KB Output is correct
77 Correct 399 ms 4216 KB Output is correct
78 Correct 403 ms 4088 KB Output is correct