Submission #53347

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
53347	2018-06-29T14:57:21 Z	junodeveloper	Boat (APIO16_boat)	C++11	100 / 100	1059 ms	11052 KB

boat

#include <bits/stdc++.h>
#define SZ(x) ((int)x.size())
#define ALL(x) (x).begin(), (x).end()
using namespace std;
typedef long long ll;
typedef long double ld;
const int MOD = 1e9 + 7;
int n, a[510], b[510];
int dp[510][1010], dp2[510][1010];
int sum[1010][510], scnt[1010][510], fac[510]={1}, inv[510]={1}, bigfac[1010][510];
vector<int> Vx;
int modpow(int a, long long n, int mod = MOD) {
	int r = 1, b = a;
	while(n > 0) {
		if(n & 1) r = 1ll * r * b % mod;
		b = 1ll * b * b % mod;
		n >>= 1;
	}
	return r;
}
int main() {
	scanf("%d", &n);
	for(int i=1; i<=n; i++) {
		scanf("%d%d", a+i, b+i); b[i]++;
		Vx.push_back(a[i]);
		Vx.push_back(b[i]);
	}
	sort(ALL(Vx));
	Vx.erase(unique(ALL(Vx)), Vx.end());
	for(int i=1; i<=500; i++) { 
		fac[i] = 1ll * fac[i-1] * i % MOD;
		inv[i] = modpow(fac[i], MOD - 2);
	}
	for(int i=1; i<SZ(Vx); i++) {
		int len = Vx[i] - Vx[i-1];
		bigfac[i][0] = 1;
		for(int j=1; j<=n; j++) {
			scnt[i][j] = scnt[i][j-1] + (min(b[j], Vx[i]) - max(a[j], Vx[i-1]) > 0);
			bigfac[i][j] = 1ll * bigfac[i][j-1] * (len - j + 1) % MOD;
		}
		for(int j=1; j<=scnt[i][n]; j++)
			for(int k=1; k<=j; k++)
				sum[i][j] = (sum[i][j] + 1ll
				* fac[j-1] * inv[k-1] % MOD * inv[j-k] % MOD
				* bigfac[i][k] % MOD * inv[k]) % MOD;
	}
	int res = 0;
	for(int i=1; i<=n; i++) {
		for(int j=1; j<SZ(Vx); j++) {
			if(!(min(b[i], Vx[j]) - max(a[i], Vx[j-1]) > 0)) continue;
			dp[i][j] = sum[j][scnt[j][i]];
			for(int k=1; k<i; k++)
				dp[i][j] = (dp[i][j] + 1ll * dp2[k][j-1] * sum[j][scnt[j][i] - scnt[j][k]]) % MOD;
			res = (res + dp[i][j]) % MOD;
		}
		for(int j=1; j<SZ(Vx); j++) dp2[i][j] = (dp2[i][j-1] + dp[i][j]) % MOD;
	}
	// sum[s][cnt] : sum(C(cnt-1, i-1) * C(Vx[s]-Vx[s-1], i)) for 1<=i<=cnt
	printf("%d", res);
	return 0;
}

Compilation message

boat.cpp: In function 'int main()':
boat.cpp:22:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &n);
  ~~~~~^~~~~~~~~~
boat.cpp:24:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d", a+i, b+i); b[i]++;
   ~~~~~^~~~~~~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	20 ms	9976 KB	Output is correct
2	Correct	20 ms	9976 KB	Output is correct
3	Correct	20 ms	10028 KB	Output is correct
4	Correct	20 ms	10080 KB	Output is correct
5	Correct	20 ms	10080 KB	Output is correct
6	Correct	20 ms	10320 KB	Output is correct
7	Correct	20 ms	10372 KB	Output is correct
8	Correct	20 ms	10408 KB	Output is correct
9	Correct	20 ms	10408 KB	Output is correct
10	Correct	20 ms	10504 KB	Output is correct
11	Correct	20 ms	10504 KB	Output is correct
12	Correct	23 ms	10504 KB	Output is correct
13	Correct	20 ms	10504 KB	Output is correct
14	Correct	20 ms	10504 KB	Output is correct
15	Correct	22 ms	10504 KB	Output is correct
16	Correct	9 ms	10504 KB	Output is correct
17	Correct	9 ms	10504 KB	Output is correct
18	Correct	10 ms	10504 KB	Output is correct
19	Correct	9 ms	10504 KB	Output is correct
20	Correct	9 ms	10504 KB	Output is correct

Subtask #2
22.0 / 22.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	20 ms	9976 KB	Output is correct
2	Correct	20 ms	9976 KB	Output is correct
3	Correct	20 ms	10028 KB	Output is correct
4	Correct	20 ms	10080 KB	Output is correct
5	Correct	20 ms	10080 KB	Output is correct
6	Correct	20 ms	10320 KB	Output is correct
7	Correct	20 ms	10372 KB	Output is correct
8	Correct	20 ms	10408 KB	Output is correct
9	Correct	20 ms	10408 KB	Output is correct
10	Correct	20 ms	10504 KB	Output is correct
11	Correct	20 ms	10504 KB	Output is correct
12	Correct	23 ms	10504 KB	Output is correct
13	Correct	20 ms	10504 KB	Output is correct
14	Correct	20 ms	10504 KB	Output is correct
15	Correct	22 ms	10504 KB	Output is correct
16	Correct	9 ms	10504 KB	Output is correct
17	Correct	9 ms	10504 KB	Output is correct
18	Correct	10 ms	10504 KB	Output is correct
19	Correct	9 ms	10504 KB	Output is correct
20	Correct	9 ms	10504 KB	Output is correct
21	Correct	497 ms	10504 KB	Output is correct
22	Correct	550 ms	10504 KB	Output is correct
23	Correct	487 ms	10504 KB	Output is correct
24	Correct	464 ms	10504 KB	Output is correct
25	Correct	498 ms	10504 KB	Output is correct
26	Correct	779 ms	10504 KB	Output is correct
27	Correct	819 ms	10504 KB	Output is correct
28	Correct	849 ms	10504 KB	Output is correct
29	Correct	815 ms	10504 KB	Output is correct
30	Correct	23 ms	10516 KB	Output is correct
31	Correct	22 ms	10516 KB	Output is correct
32	Correct	20 ms	10516 KB	Output is correct
33	Correct	21 ms	10516 KB	Output is correct
34	Correct	21 ms	10516 KB	Output is correct
35	Correct	22 ms	10516 KB	Output is correct
36	Correct	23 ms	10516 KB	Output is correct
37	Correct	21 ms	10516 KB	Output is correct
38	Correct	24 ms	10516 KB	Output is correct

Subtask #3
27.0 / 27.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	9 ms	10516 KB	Output is correct
2	Correct	7 ms	10516 KB	Output is correct
3	Correct	8 ms	10516 KB	Output is correct
4	Correct	9 ms	10516 KB	Output is correct
5	Correct	10 ms	10516 KB	Output is correct
6	Correct	11 ms	10516 KB	Output is correct
7	Correct	12 ms	10516 KB	Output is correct
8	Correct	14 ms	10516 KB	Output is correct
9	Correct	12 ms	10516 KB	Output is correct
10	Correct	11 ms	10516 KB	Output is correct
11	Correct	8 ms	10516 KB	Output is correct
12	Correct	8 ms	10516 KB	Output is correct
13	Correct	8 ms	10516 KB	Output is correct
14	Correct	7 ms	10516 KB	Output is correct
15	Correct	9 ms	10516 KB	Output is correct
16	Correct	7 ms	10516 KB	Output is correct
17	Correct	8 ms	10516 KB	Output is correct
18	Correct	6 ms	10516 KB	Output is correct
19	Correct	6 ms	10516 KB	Output is correct
20	Correct	6 ms	10516 KB	Output is correct

Subtask #4
42.0 / 42.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	20 ms	9976 KB	Output is correct
2	Correct	20 ms	9976 KB	Output is correct
3	Correct	20 ms	10028 KB	Output is correct
4	Correct	20 ms	10080 KB	Output is correct
5	Correct	20 ms	10080 KB	Output is correct
6	Correct	20 ms	10320 KB	Output is correct
7	Correct	20 ms	10372 KB	Output is correct
8	Correct	20 ms	10408 KB	Output is correct
9	Correct	20 ms	10408 KB	Output is correct
10	Correct	20 ms	10504 KB	Output is correct
11	Correct	20 ms	10504 KB	Output is correct
12	Correct	23 ms	10504 KB	Output is correct
13	Correct	20 ms	10504 KB	Output is correct
14	Correct	20 ms	10504 KB	Output is correct
15	Correct	22 ms	10504 KB	Output is correct
16	Correct	9 ms	10504 KB	Output is correct
17	Correct	9 ms	10504 KB	Output is correct
18	Correct	10 ms	10504 KB	Output is correct
19	Correct	9 ms	10504 KB	Output is correct
20	Correct	9 ms	10504 KB	Output is correct
21	Correct	497 ms	10504 KB	Output is correct
22	Correct	550 ms	10504 KB	Output is correct
23	Correct	487 ms	10504 KB	Output is correct
24	Correct	464 ms	10504 KB	Output is correct
25	Correct	498 ms	10504 KB	Output is correct
26	Correct	779 ms	10504 KB	Output is correct
27	Correct	819 ms	10504 KB	Output is correct
28	Correct	849 ms	10504 KB	Output is correct
29	Correct	815 ms	10504 KB	Output is correct
30	Correct	23 ms	10516 KB	Output is correct
31	Correct	22 ms	10516 KB	Output is correct
32	Correct	20 ms	10516 KB	Output is correct
33	Correct	21 ms	10516 KB	Output is correct
34	Correct	21 ms	10516 KB	Output is correct
35	Correct	22 ms	10516 KB	Output is correct
36	Correct	23 ms	10516 KB	Output is correct
37	Correct	21 ms	10516 KB	Output is correct
38	Correct	24 ms	10516 KB	Output is correct
39	Correct	9 ms	10516 KB	Output is correct
40	Correct	7 ms	10516 KB	Output is correct
41	Correct	8 ms	10516 KB	Output is correct
42	Correct	9 ms	10516 KB	Output is correct
43	Correct	10 ms	10516 KB	Output is correct
44	Correct	11 ms	10516 KB	Output is correct
45	Correct	12 ms	10516 KB	Output is correct
46	Correct	14 ms	10516 KB	Output is correct
47	Correct	12 ms	10516 KB	Output is correct
48	Correct	11 ms	10516 KB	Output is correct
49	Correct	8 ms	10516 KB	Output is correct
50	Correct	8 ms	10516 KB	Output is correct
51	Correct	8 ms	10516 KB	Output is correct
52	Correct	7 ms	10516 KB	Output is correct
53	Correct	9 ms	10516 KB	Output is correct
54	Correct	7 ms	10516 KB	Output is correct
55	Correct	8 ms	10516 KB	Output is correct
56	Correct	6 ms	10516 KB	Output is correct
57	Correct	6 ms	10516 KB	Output is correct
58	Correct	6 ms	10516 KB	Output is correct
59	Correct	621 ms	10516 KB	Output is correct
60	Correct	555 ms	10568 KB	Output is correct
61	Correct	493 ms	10604 KB	Output is correct
62	Correct	532 ms	10604 KB	Output is correct
63	Correct	593 ms	10720 KB	Output is correct
64	Correct	928 ms	10756 KB	Output is correct
65	Correct	1046 ms	10856 KB	Output is correct
66	Correct	1059 ms	11052 KB	Output is correct
67	Correct	946 ms	11052 KB	Output is correct
68	Correct	978 ms	11052 KB	Output is correct
69	Correct	394 ms	11052 KB	Output is correct
70	Correct	435 ms	11052 KB	Output is correct
71	Correct	427 ms	11052 KB	Output is correct
72	Correct	421 ms	11052 KB	Output is correct
73	Correct	435 ms	11052 KB	Output is correct
74	Correct	96 ms	11052 KB	Output is correct
75	Correct	93 ms	11052 KB	Output is correct
76	Correct	97 ms	11052 KB	Output is correct
77	Correct	97 ms	11052 KB	Output is correct
78	Correct	104 ms	11052 KB	Output is correct

Submission #53347

Compilation message

Subtask #1 9.0 / 9.0

Subtask #2 22.0 / 22.0

Subtask #3 27.0 / 27.0

Subtask #4 42.0 / 42.0

Subtask #1
9.0 / 9.0

Subtask #2
22.0 / 22.0

Subtask #3
27.0 / 27.0

Subtask #4
42.0 / 42.0