oj.uz

Submission #200601

# Submission time Handle Problem Language Result Execution time Memory
200601 2020-02-07T14:15:06 Z dennisstar Boat (APIO16_boat) C++17
9 / 100
 185 ms 4348 KB 
#include <bits/stdc++.h>
#define eb emplace_back
#define all(V) (V).begin(), (V).end()
#define unq(V) (V).erase(unique(all(V)), (V).end())
using namespace std;
typedef long long ll;
typedef vector<int> vim;

const ll MOD = 1e9+7;

ll getinv(ll x) {
	ll ret=1;
	for (int i=30; i>=0; i--) {
		ret=ret*ret%MOD;
		if ((1<<i)&(MOD-2)) ret=ret*x%MOD;
	}
	return ret;
}

int N, A[505], B[505]; vim cp;
ll D[505][1010], L[1010], inv[505];

int main() {
	for (int i=1; i<=500; i++) inv[i]=getinv(i);

	scanf("%d", &N);
	for (int i=1; i<=N; i++) scanf("%d %d", &A[i], &B[i]), cp.eb(A[i]), cp.eb(B[i]+1);
	sort(all(cp)); unq(cp);
	for (int i=1; i<=N; i++) A[i]=upper_bound(all(cp), A[i])-cp.begin();
	for (int i=1; i<=N; i++) B[i]=upper_bound(all(cp), B[i])-cp.begin();
	for (int i=1; i<cp.size(); i++) L[i]=cp[i]-cp[i-1];
	fill(D[0], D[0]+1010, 1);

	for (int i=1; i<=N; i++) {
		D[i][0]=1;
		for (int j=A[i]; j<=B[i]; j++) {
			D[i][j]=D[i-1][j-1]*L[j]%MOD;
			int cnt=1, num=L[j]-1;
			for (int k=i-1; k; k--) if (A[k]<=j&&j<=B[k]) {
				cnt++;
				num*=(L[j]+cnt-2)*inv[cnt]%MOD; num%=MOD;
				D[i][j]+=D[k-1][j-1]*num; D[i][j]%=MOD;
			}
		}
		for (int j=1; j<cp.size(); j++) D[i][j]+=D[i-1][j]+D[i][j-1]-D[i-1][j-1]+MOD, D[i][j]%=MOD;
	}

	printf("%lld\n", (D[N][cp.size()-1]+MOD-1)%MOD);
	return 0;
}

Compilation message

boat.cpp: In function 'int main()':
boat.cpp:31:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i=1; i<cp.size(); i++) L[i]=cp[i]-cp[i-1];
                ~^~~~~~~~~~
boat.cpp:45:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int j=1; j<cp.size(); j++) D[i][j]+=D[i-1][j]+D[i][j-1]-D[i-1][j-1]+MOD, D[i][j]%=MOD;
                 ~^~~~~~~~~~
boat.cpp:26:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &N);
  ~~~~~^~~~~~~~~~
boat.cpp:27:68: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  for (int i=1; i<=N; i++) scanf("%d %d", &A[i], &B[i]), cp.eb(A[i]), cp.eb(B[i]+1);
                           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 4344 KB Output is correct
2 Correct 12 ms 4344 KB Output is correct
3 Correct 13 ms 4344 KB Output is correct
4 Correct 12 ms 4216 KB Output is correct
5 Correct 12 ms 4344 KB Output is correct
6 Correct 12 ms 4344 KB Output is correct
7 Correct 12 ms 4344 KB Output is correct
8 Correct 12 ms 4348 KB Output is correct
9 Correct 13 ms 4344 KB Output is correct
10 Correct 12 ms 4216 KB Output is correct
11 Correct 12 ms 4344 KB Output is correct
12 Correct 19 ms 4344 KB Output is correct
13 Correct 12 ms 4344 KB Output is correct
14 Correct 12 ms 4344 KB Output is correct
15 Correct 12 ms 4344 KB Output is correct
16 Correct 8 ms 2936 KB Output is correct
17 Correct 8 ms 3064 KB Output is correct
18 Correct 8 ms 3064 KB Output is correct
19 Correct 8 ms 3064 KB Output is correct
20 Correct 8 ms 3064 KB Output is correct

Subtask #2
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 4344 KB Output is correct
2 Correct 12 ms 4344 KB Output is correct
3 Correct 13 ms 4344 KB Output is correct
4 Correct 12 ms 4216 KB Output is correct
5 Correct 12 ms 4344 KB Output is correct
6 Correct 12 ms 4344 KB Output is correct
7 Correct 12 ms 4344 KB Output is correct
8 Correct 12 ms 4348 KB Output is correct
9 Correct 13 ms 4344 KB Output is correct
10 Correct 12 ms 4216 KB Output is correct
11 Correct 12 ms 4344 KB Output is correct
12 Correct 19 ms 4344 KB Output is correct
13 Correct 12 ms 4344 KB Output is correct
14 Correct 12 ms 4344 KB Output is correct
15 Correct 12 ms 4344 KB Output is correct
16 Correct 8 ms 2936 KB Output is correct
17 Correct 8 ms 3064 KB Output is correct
18 Correct 8 ms 3064 KB Output is correct
19 Correct 8 ms 3064 KB Output is correct
20 Correct 8 ms 3064 KB Output is correct
21 Incorrect 185 ms 4344 KB Output isn't correct
22 Halted 0 ms 0 KB -

Subtask #3
0 / 27.0

# Verdict Execution time Memory Grader output
1 Incorrect 7 ms 888 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 42.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 4344 KB Output is correct
2 Correct 12 ms 4344 KB Output is correct
3 Correct 13 ms 4344 KB Output is correct
4 Correct 12 ms 4216 KB Output is correct
5 Correct 12 ms 4344 KB Output is correct
6 Correct 12 ms 4344 KB Output is correct
7 Correct 12 ms 4344 KB Output is correct
8 Correct 12 ms 4348 KB Output is correct
9 Correct 13 ms 4344 KB Output is correct
10 Correct 12 ms 4216 KB Output is correct
11 Correct 12 ms 4344 KB Output is correct
12 Correct 19 ms 4344 KB Output is correct
13 Correct 12 ms 4344 KB Output is correct
14 Correct 12 ms 4344 KB Output is correct
15 Correct 12 ms 4344 KB Output is correct
16 Correct 8 ms 2936 KB Output is correct
17 Correct 8 ms 3064 KB Output is correct
18 Correct 8 ms 3064 KB Output is correct
19 Correct 8 ms 3064 KB Output is correct
20 Correct 8 ms 3064 KB Output is correct
21 Incorrect 185 ms 4344 KB Output isn't correct
22 Halted 0 ms 0 KB -