#include<bits/stdc++.h>
#define fi first
#define se second
#define all(x) (x).begin() , (x).end()
#define rall(x) (x).rbegin() , (x).rend()
#define mkp make_pair
#define pb push_back
#define len(x) (int)(x).size()
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
//#define int long long
const int MOD = (int)1e9 + 7, N = 502 , NN = 1001;
int pw(int a , int b){
if(b == 0)return 1;
int ans = pw(a , b >> 1);
ans = (1ll * ans * ans) % MOD;
if(b & 1)
ans = (1ll * ans * a) % MOD;
return ans;
}
int f[4*N][N] , inv[N] , fact[N];
int C[N][N] , done[4*N][N] , cnt[4*N][N];
void md(int &a){
if(a >= MOD)a-=MOD;
}
void COMBA(vector<pii>&lines){
fact[0] = 1;
for(int i = 1 ; i < N; ++i)
fact[i] = (1ll * fact[i-1] * i) % MOD;
inv[N-1] = pw(fact[N-1], MOD-2);
for(int i = N-2;i>=0;--i)
inv[i] = (1ll * inv[i+1]*(i+1))%MOD;
for(int i = 0 ; i < N; ++i){
C[i][0] = 1;
for(int j = 1; j <= i ; ++j){
C[i][j] = C[i-1][j] + C[i-1][j-1];
md(C[i][j]);
}
}
/// fucking cnt[i][j]
for(int i = 1; i < len(lines); ++i){
for(int want = 0 ;want < N; ++want){
int len = lines[i].se - lines[i].fi + 1;
if(len < want)
done[i][want] = 0;
else{
ll answer = 1;
for(int j = len-want + 1; j<= len; ++j){
answer = (1ll * answer * j) % MOD;
}
answer = (1ll * answer * inv[want]) % MOD;
done[i][want] = answer;
}
}
}
for(int i = 0 ; i < len(lines); ++i){
for(int j = 1 ; j < N; ++j){
for(int k = 0 ; k < j; ++k){
cnt[i][j] += (1ll * C[j-1][k] * done[i][j-k])%MOD;
md(cnt[i][j]);
}
}
}
}
signed main(){
// ifstream cin("1_01.in");
ios_base::sync_with_stdio(0) , cin.tie(0) , cout.tie(0);
int n;cin >> n;
vector<pii>boats(n);
for(auto&i:boats)cin>>i.fi>>i.se;
/// lulz wtf is going on here
set < int > dots;
for(auto x : boats)
dots.insert(x.fi) , dots.insert(x.se);
vector<pii>lines;
lines.pb({0 , 0});
for(auto i : dots)
lines.pb(mkp(i , i));
auto it = dots.begin();
int prev = *it;
++it;
while(it != dots.end()){
if(prev + 1 <= *it-1)
lines.pb({prev + 1 , *it-1});
prev = *it;
++it;
}
sort(all(lines));
for(auto &i : boats){
int l = lower_bound(all(lines) , mkp(i.fi , -1))-lines.begin();
int r = lower_bound(all(lines) , mkp(i.se + 1 , -1))-lines.begin() - 1;
i = mkp(l , r);
}
COMBA(lines);
for(int i = 0 ; i < n; ++i)
f[0][i] = 1;
for(int i = 1; i < len(lines); ++i){
for(int j = 0; j < N; ++j)
f[i][j] = f[i-1][j];
/// what if we skip anybody
for(int j = 1; j <= n; ++j){
int cur = j;
int bad = 0;
for(int k = 1; k <= n , cur>0; ++k , --cur){
if(boats[cur-1].se < i || boats[cur-1].fi > i)
{bad++;continue;}
/// firstly update answer
f[i][j] += (f[i-1][j-k]*1ll*cnt[i][k - bad])%MOD;
md(f[i][j]);
}
}
// cout << " I " << i << '\n';
// for(int j = 0 ; j <= n; ++j)
// cout << f[i][j] << ' ' ;
// cout << '\n';
}
cout << f[len(lines)-1][n];
return 0;
}
Compilation message
boat.cpp: In function 'int main()':
boat.cpp:117:30: warning: left operand of comma operator has no effect [-Wunused-value]
for(int k = 1; k <= n , cur>0; ++k , --cur){
~~^~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1053 ms |
7392 KB |
Output is correct |
2 |
Correct |
1057 ms |
7288 KB |
Output is correct |
3 |
Correct |
1062 ms |
7416 KB |
Output is correct |
4 |
Correct |
1058 ms |
7312 KB |
Output is correct |
5 |
Correct |
1059 ms |
7468 KB |
Output is correct |
6 |
Correct |
967 ms |
7416 KB |
Output is correct |
7 |
Correct |
967 ms |
7288 KB |
Output is correct |
8 |
Correct |
956 ms |
7416 KB |
Output is correct |
9 |
Correct |
965 ms |
7516 KB |
Output is correct |
10 |
Correct |
968 ms |
7416 KB |
Output is correct |
11 |
Correct |
958 ms |
7544 KB |
Output is correct |
12 |
Correct |
973 ms |
7288 KB |
Output is correct |
13 |
Correct |
953 ms |
7288 KB |
Output is correct |
14 |
Correct |
965 ms |
7288 KB |
Output is correct |
15 |
Correct |
961 ms |
7288 KB |
Output is correct |
16 |
Correct |
188 ms |
2424 KB |
Output is correct |
17 |
Correct |
200 ms |
2744 KB |
Output is correct |
18 |
Correct |
192 ms |
2424 KB |
Output is correct |
19 |
Correct |
200 ms |
2552 KB |
Output is correct |
20 |
Correct |
194 ms |
2424 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1053 ms |
7392 KB |
Output is correct |
2 |
Correct |
1057 ms |
7288 KB |
Output is correct |
3 |
Correct |
1062 ms |
7416 KB |
Output is correct |
4 |
Correct |
1058 ms |
7312 KB |
Output is correct |
5 |
Correct |
1059 ms |
7468 KB |
Output is correct |
6 |
Correct |
967 ms |
7416 KB |
Output is correct |
7 |
Correct |
967 ms |
7288 KB |
Output is correct |
8 |
Correct |
956 ms |
7416 KB |
Output is correct |
9 |
Correct |
965 ms |
7516 KB |
Output is correct |
10 |
Correct |
968 ms |
7416 KB |
Output is correct |
11 |
Correct |
958 ms |
7544 KB |
Output is correct |
12 |
Correct |
973 ms |
7288 KB |
Output is correct |
13 |
Correct |
953 ms |
7288 KB |
Output is correct |
14 |
Correct |
965 ms |
7288 KB |
Output is correct |
15 |
Correct |
961 ms |
7288 KB |
Output is correct |
16 |
Correct |
188 ms |
2424 KB |
Output is correct |
17 |
Correct |
200 ms |
2744 KB |
Output is correct |
18 |
Correct |
192 ms |
2424 KB |
Output is correct |
19 |
Correct |
200 ms |
2552 KB |
Output is correct |
20 |
Correct |
194 ms |
2424 KB |
Output is correct |
21 |
Correct |
1402 ms |
11384 KB |
Output is correct |
22 |
Correct |
1411 ms |
11256 KB |
Output is correct |
23 |
Correct |
1374 ms |
11128 KB |
Output is correct |
24 |
Correct |
1414 ms |
11256 KB |
Output is correct |
25 |
Correct |
1397 ms |
11136 KB |
Output is correct |
26 |
Correct |
1449 ms |
10616 KB |
Output is correct |
27 |
Correct |
1447 ms |
10824 KB |
Output is correct |
28 |
Correct |
1441 ms |
10656 KB |
Output is correct |
29 |
Correct |
1448 ms |
10864 KB |
Output is correct |
30 |
Correct |
1510 ms |
12372 KB |
Output is correct |
31 |
Correct |
1498 ms |
12420 KB |
Output is correct |
32 |
Correct |
1506 ms |
12408 KB |
Output is correct |
33 |
Correct |
1493 ms |
12312 KB |
Output is correct |
34 |
Correct |
1495 ms |
12388 KB |
Output is correct |
35 |
Correct |
1030 ms |
7416 KB |
Output is correct |
36 |
Correct |
1034 ms |
7272 KB |
Output is correct |
37 |
Correct |
1041 ms |
7336 KB |
Output is correct |
38 |
Correct |
1032 ms |
7416 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
346 ms |
3848 KB |
Output is correct |
2 |
Correct |
343 ms |
3704 KB |
Output is correct |
3 |
Correct |
346 ms |
3764 KB |
Output is correct |
4 |
Correct |
344 ms |
3736 KB |
Output is correct |
5 |
Correct |
343 ms |
3832 KB |
Output is correct |
6 |
Correct |
347 ms |
3704 KB |
Output is correct |
7 |
Correct |
345 ms |
3708 KB |
Output is correct |
8 |
Correct |
348 ms |
3832 KB |
Output is correct |
9 |
Correct |
344 ms |
3704 KB |
Output is correct |
10 |
Correct |
346 ms |
3704 KB |
Output is correct |
11 |
Correct |
342 ms |
3704 KB |
Output is correct |
12 |
Correct |
347 ms |
3872 KB |
Output is correct |
13 |
Correct |
340 ms |
3704 KB |
Output is correct |
14 |
Correct |
346 ms |
3704 KB |
Output is correct |
15 |
Correct |
345 ms |
3704 KB |
Output is correct |
16 |
Correct |
153 ms |
2424 KB |
Output is correct |
17 |
Correct |
152 ms |
2508 KB |
Output is correct |
18 |
Correct |
152 ms |
2424 KB |
Output is correct |
19 |
Correct |
153 ms |
2424 KB |
Output is correct |
20 |
Correct |
159 ms |
2552 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1053 ms |
7392 KB |
Output is correct |
2 |
Correct |
1057 ms |
7288 KB |
Output is correct |
3 |
Correct |
1062 ms |
7416 KB |
Output is correct |
4 |
Correct |
1058 ms |
7312 KB |
Output is correct |
5 |
Correct |
1059 ms |
7468 KB |
Output is correct |
6 |
Correct |
967 ms |
7416 KB |
Output is correct |
7 |
Correct |
967 ms |
7288 KB |
Output is correct |
8 |
Correct |
956 ms |
7416 KB |
Output is correct |
9 |
Correct |
965 ms |
7516 KB |
Output is correct |
10 |
Correct |
968 ms |
7416 KB |
Output is correct |
11 |
Correct |
958 ms |
7544 KB |
Output is correct |
12 |
Correct |
973 ms |
7288 KB |
Output is correct |
13 |
Correct |
953 ms |
7288 KB |
Output is correct |
14 |
Correct |
965 ms |
7288 KB |
Output is correct |
15 |
Correct |
961 ms |
7288 KB |
Output is correct |
16 |
Correct |
188 ms |
2424 KB |
Output is correct |
17 |
Correct |
200 ms |
2744 KB |
Output is correct |
18 |
Correct |
192 ms |
2424 KB |
Output is correct |
19 |
Correct |
200 ms |
2552 KB |
Output is correct |
20 |
Correct |
194 ms |
2424 KB |
Output is correct |
21 |
Correct |
1402 ms |
11384 KB |
Output is correct |
22 |
Correct |
1411 ms |
11256 KB |
Output is correct |
23 |
Correct |
1374 ms |
11128 KB |
Output is correct |
24 |
Correct |
1414 ms |
11256 KB |
Output is correct |
25 |
Correct |
1397 ms |
11136 KB |
Output is correct |
26 |
Correct |
1449 ms |
10616 KB |
Output is correct |
27 |
Correct |
1447 ms |
10824 KB |
Output is correct |
28 |
Correct |
1441 ms |
10656 KB |
Output is correct |
29 |
Correct |
1448 ms |
10864 KB |
Output is correct |
30 |
Correct |
1510 ms |
12372 KB |
Output is correct |
31 |
Correct |
1498 ms |
12420 KB |
Output is correct |
32 |
Correct |
1506 ms |
12408 KB |
Output is correct |
33 |
Correct |
1493 ms |
12312 KB |
Output is correct |
34 |
Correct |
1495 ms |
12388 KB |
Output is correct |
35 |
Correct |
1030 ms |
7416 KB |
Output is correct |
36 |
Correct |
1034 ms |
7272 KB |
Output is correct |
37 |
Correct |
1041 ms |
7336 KB |
Output is correct |
38 |
Correct |
1032 ms |
7416 KB |
Output is correct |
39 |
Correct |
346 ms |
3848 KB |
Output is correct |
40 |
Correct |
343 ms |
3704 KB |
Output is correct |
41 |
Correct |
346 ms |
3764 KB |
Output is correct |
42 |
Correct |
344 ms |
3736 KB |
Output is correct |
43 |
Correct |
343 ms |
3832 KB |
Output is correct |
44 |
Correct |
347 ms |
3704 KB |
Output is correct |
45 |
Correct |
345 ms |
3708 KB |
Output is correct |
46 |
Correct |
348 ms |
3832 KB |
Output is correct |
47 |
Correct |
344 ms |
3704 KB |
Output is correct |
48 |
Correct |
346 ms |
3704 KB |
Output is correct |
49 |
Correct |
342 ms |
3704 KB |
Output is correct |
50 |
Correct |
347 ms |
3872 KB |
Output is correct |
51 |
Correct |
340 ms |
3704 KB |
Output is correct |
52 |
Correct |
346 ms |
3704 KB |
Output is correct |
53 |
Correct |
345 ms |
3704 KB |
Output is correct |
54 |
Correct |
153 ms |
2424 KB |
Output is correct |
55 |
Correct |
152 ms |
2508 KB |
Output is correct |
56 |
Correct |
152 ms |
2424 KB |
Output is correct |
57 |
Correct |
153 ms |
2424 KB |
Output is correct |
58 |
Correct |
159 ms |
2552 KB |
Output is correct |
59 |
Execution timed out |
2082 ms |
11716 KB |
Time limit exceeded |
60 |
Halted |
0 ms |
0 KB |
- |