#include<bits/stdc++.h>
using namespace std;
const int nax = 503;
const int mod = 1e9 + 7;
const int cax = 1e6 + 3;
const long long sux = 1361;
vector<int>ind[nax*2];
int a[nax], b[nax];
int n, m;
int dp[nax*2][nax];
int inv[nax];
vector<int>imp;
int add(int a, int b) {
a += b;
if(a>=mod) a -= mod;
return a;
}
int mul(int a, int b) {
return (a * 1LL * b) % mod;
}
int quickpow(int a, int b) {
int ret = 1;
while(b) {
if(b&1) ret = mul(ret, a);
a = mul(a, a);
b >>= 1;
}
return ret;
}
int get(int x) {
int &ret = inv[x];
if(ret==-1) {
ret = quickpow(x, mod-2);
}
return ret;
}
vector<pair<long long,int>>table[cax];
int C(int n, int r) {
long long H = n * sux + r;
int H2 = H % cax;
for(auto x : table[H2]) {
if(x.first==H) return x.second;
}
int ret = 1;
for(int i=n-r+1; i<=n; ++i) {
ret = mul(ret, i);
}
for(int i=1; i<=r; ++i) {
ret = mul(ret, get(i));
}
table[H2].emplace_back(H, ret);
return ret;
}
vector<pair<long long,int>>andp[cax];
int get(int len, int op) {
long long H = len * sux + op;
int H2 = H % cax;
for(auto x : andp[H2]) {
if(x.first==H) return x.second;
}
int ret = 0;
for(int take=0; take<=min(op, len-1); ++take) {
ret = add(ret, mul(C(op, take), C(len, take+1)));
}
andp[H2].emplace_back(H, ret);
return ret;
}
int solve(int i, int prv) {
if(i==m-1) return prv>0;
int &ret = dp[i][prv];
if(ret!=-1) return ret;
ret = 0;
ret = solve(i+1, prv);
int len = imp[i+1]-imp[i];
for(int mx=0, cur_op=0; mx<ind[i].size(); ++mx) {
if(ind[i][mx]<=prv) continue;
int cur = mul(solve(i+1, ind[i][mx]), get(len, cur_op));
cur_op++;
ret = add(ret, cur);
}
return ret;
}
void PlayGround() {
cin>>n;
set<int>pts;
for(int i=1; i<=n; ++i) {
cin>>a[i]>>b[i];
pts.insert(a[i]);
pts.insert(b[i]+1);
}
for(int x : pts) {
imp.push_back(x);
}
m = imp.size();
for(int i=0; i<m; ++i) {
for(int j=1; j<=n; ++j) {
if(imp[i]>=a[j] && imp[i]<=b[j]) {
ind[i].push_back(j);
}
}
}
memset(inv, -1, sizeof inv);
memset(dp, -1, sizeof dp);
cout<<solve(0, 0)<<'\n';
// cerr << "Time elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n";
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
PlayGround();
return 0;
}
Compilation message
boat.cpp: In function 'int solve(int, int)':
boat.cpp:86:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
86 | for(int mx=0, cur_op=0; mx<ind[i].size(); ++mx) {
| ~~^~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
28 ms |
49456 KB |
Output is correct |
2 |
Correct |
28 ms |
49428 KB |
Output is correct |
3 |
Correct |
30 ms |
49464 KB |
Output is correct |
4 |
Correct |
28 ms |
49332 KB |
Output is correct |
5 |
Correct |
28 ms |
49432 KB |
Output is correct |
6 |
Correct |
28 ms |
49348 KB |
Output is correct |
7 |
Correct |
28 ms |
49480 KB |
Output is correct |
8 |
Correct |
28 ms |
49456 KB |
Output is correct |
9 |
Correct |
29 ms |
49360 KB |
Output is correct |
10 |
Correct |
29 ms |
49440 KB |
Output is correct |
11 |
Correct |
31 ms |
49424 KB |
Output is correct |
12 |
Correct |
29 ms |
49416 KB |
Output is correct |
13 |
Correct |
29 ms |
49480 KB |
Output is correct |
14 |
Correct |
28 ms |
49364 KB |
Output is correct |
15 |
Correct |
31 ms |
49420 KB |
Output is correct |
16 |
Correct |
26 ms |
49312 KB |
Output is correct |
17 |
Correct |
26 ms |
49412 KB |
Output is correct |
18 |
Correct |
25 ms |
49256 KB |
Output is correct |
19 |
Correct |
26 ms |
49332 KB |
Output is correct |
20 |
Correct |
25 ms |
49212 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
28 ms |
49456 KB |
Output is correct |
2 |
Correct |
28 ms |
49428 KB |
Output is correct |
3 |
Correct |
30 ms |
49464 KB |
Output is correct |
4 |
Correct |
28 ms |
49332 KB |
Output is correct |
5 |
Correct |
28 ms |
49432 KB |
Output is correct |
6 |
Correct |
28 ms |
49348 KB |
Output is correct |
7 |
Correct |
28 ms |
49480 KB |
Output is correct |
8 |
Correct |
28 ms |
49456 KB |
Output is correct |
9 |
Correct |
29 ms |
49360 KB |
Output is correct |
10 |
Correct |
29 ms |
49440 KB |
Output is correct |
11 |
Correct |
31 ms |
49424 KB |
Output is correct |
12 |
Correct |
29 ms |
49416 KB |
Output is correct |
13 |
Correct |
29 ms |
49480 KB |
Output is correct |
14 |
Correct |
28 ms |
49364 KB |
Output is correct |
15 |
Correct |
31 ms |
49420 KB |
Output is correct |
16 |
Correct |
26 ms |
49312 KB |
Output is correct |
17 |
Correct |
26 ms |
49412 KB |
Output is correct |
18 |
Correct |
25 ms |
49256 KB |
Output is correct |
19 |
Correct |
26 ms |
49332 KB |
Output is correct |
20 |
Correct |
25 ms |
49212 KB |
Output is correct |
21 |
Correct |
314 ms |
50568 KB |
Output is correct |
22 |
Correct |
296 ms |
50940 KB |
Output is correct |
23 |
Correct |
277 ms |
50600 KB |
Output is correct |
24 |
Correct |
291 ms |
50688 KB |
Output is correct |
25 |
Correct |
298 ms |
50712 KB |
Output is correct |
26 |
Correct |
558 ms |
51332 KB |
Output is correct |
27 |
Correct |
569 ms |
51240 KB |
Output is correct |
28 |
Correct |
580 ms |
51420 KB |
Output is correct |
29 |
Correct |
546 ms |
51292 KB |
Output is correct |
30 |
Correct |
32 ms |
49492 KB |
Output is correct |
31 |
Correct |
31 ms |
49444 KB |
Output is correct |
32 |
Correct |
34 ms |
49488 KB |
Output is correct |
33 |
Correct |
33 ms |
49508 KB |
Output is correct |
34 |
Correct |
33 ms |
49484 KB |
Output is correct |
35 |
Correct |
30 ms |
49520 KB |
Output is correct |
36 |
Correct |
35 ms |
49512 KB |
Output is correct |
37 |
Correct |
32 ms |
49612 KB |
Output is correct |
38 |
Correct |
31 ms |
49492 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
39 ms |
49696 KB |
Output is correct |
2 |
Correct |
31 ms |
49620 KB |
Output is correct |
3 |
Correct |
31 ms |
49784 KB |
Output is correct |
4 |
Correct |
31 ms |
49804 KB |
Output is correct |
5 |
Correct |
37 ms |
49796 KB |
Output is correct |
6 |
Correct |
40 ms |
50120 KB |
Output is correct |
7 |
Correct |
41 ms |
50040 KB |
Output is correct |
8 |
Correct |
40 ms |
50128 KB |
Output is correct |
9 |
Correct |
47 ms |
50100 KB |
Output is correct |
10 |
Correct |
40 ms |
50124 KB |
Output is correct |
11 |
Correct |
32 ms |
49780 KB |
Output is correct |
12 |
Correct |
29 ms |
49740 KB |
Output is correct |
13 |
Correct |
31 ms |
49796 KB |
Output is correct |
14 |
Correct |
32 ms |
49748 KB |
Output is correct |
15 |
Correct |
34 ms |
49748 KB |
Output is correct |
16 |
Correct |
27 ms |
49504 KB |
Output is correct |
17 |
Correct |
27 ms |
49492 KB |
Output is correct |
18 |
Correct |
27 ms |
49548 KB |
Output is correct |
19 |
Correct |
29 ms |
49416 KB |
Output is correct |
20 |
Correct |
28 ms |
49540 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
28 ms |
49456 KB |
Output is correct |
2 |
Correct |
28 ms |
49428 KB |
Output is correct |
3 |
Correct |
30 ms |
49464 KB |
Output is correct |
4 |
Correct |
28 ms |
49332 KB |
Output is correct |
5 |
Correct |
28 ms |
49432 KB |
Output is correct |
6 |
Correct |
28 ms |
49348 KB |
Output is correct |
7 |
Correct |
28 ms |
49480 KB |
Output is correct |
8 |
Correct |
28 ms |
49456 KB |
Output is correct |
9 |
Correct |
29 ms |
49360 KB |
Output is correct |
10 |
Correct |
29 ms |
49440 KB |
Output is correct |
11 |
Correct |
31 ms |
49424 KB |
Output is correct |
12 |
Correct |
29 ms |
49416 KB |
Output is correct |
13 |
Correct |
29 ms |
49480 KB |
Output is correct |
14 |
Correct |
28 ms |
49364 KB |
Output is correct |
15 |
Correct |
31 ms |
49420 KB |
Output is correct |
16 |
Correct |
26 ms |
49312 KB |
Output is correct |
17 |
Correct |
26 ms |
49412 KB |
Output is correct |
18 |
Correct |
25 ms |
49256 KB |
Output is correct |
19 |
Correct |
26 ms |
49332 KB |
Output is correct |
20 |
Correct |
25 ms |
49212 KB |
Output is correct |
21 |
Correct |
314 ms |
50568 KB |
Output is correct |
22 |
Correct |
296 ms |
50940 KB |
Output is correct |
23 |
Correct |
277 ms |
50600 KB |
Output is correct |
24 |
Correct |
291 ms |
50688 KB |
Output is correct |
25 |
Correct |
298 ms |
50712 KB |
Output is correct |
26 |
Correct |
558 ms |
51332 KB |
Output is correct |
27 |
Correct |
569 ms |
51240 KB |
Output is correct |
28 |
Correct |
580 ms |
51420 KB |
Output is correct |
29 |
Correct |
546 ms |
51292 KB |
Output is correct |
30 |
Correct |
32 ms |
49492 KB |
Output is correct |
31 |
Correct |
31 ms |
49444 KB |
Output is correct |
32 |
Correct |
34 ms |
49488 KB |
Output is correct |
33 |
Correct |
33 ms |
49508 KB |
Output is correct |
34 |
Correct |
33 ms |
49484 KB |
Output is correct |
35 |
Correct |
30 ms |
49520 KB |
Output is correct |
36 |
Correct |
35 ms |
49512 KB |
Output is correct |
37 |
Correct |
32 ms |
49612 KB |
Output is correct |
38 |
Correct |
31 ms |
49492 KB |
Output is correct |
39 |
Correct |
39 ms |
49696 KB |
Output is correct |
40 |
Correct |
31 ms |
49620 KB |
Output is correct |
41 |
Correct |
31 ms |
49784 KB |
Output is correct |
42 |
Correct |
31 ms |
49804 KB |
Output is correct |
43 |
Correct |
37 ms |
49796 KB |
Output is correct |
44 |
Correct |
40 ms |
50120 KB |
Output is correct |
45 |
Correct |
41 ms |
50040 KB |
Output is correct |
46 |
Correct |
40 ms |
50128 KB |
Output is correct |
47 |
Correct |
47 ms |
50100 KB |
Output is correct |
48 |
Correct |
40 ms |
50124 KB |
Output is correct |
49 |
Correct |
32 ms |
49780 KB |
Output is correct |
50 |
Correct |
29 ms |
49740 KB |
Output is correct |
51 |
Correct |
31 ms |
49796 KB |
Output is correct |
52 |
Correct |
32 ms |
49748 KB |
Output is correct |
53 |
Correct |
34 ms |
49748 KB |
Output is correct |
54 |
Correct |
27 ms |
49504 KB |
Output is correct |
55 |
Correct |
27 ms |
49492 KB |
Output is correct |
56 |
Correct |
27 ms |
49548 KB |
Output is correct |
57 |
Correct |
29 ms |
49416 KB |
Output is correct |
58 |
Correct |
28 ms |
49540 KB |
Output is correct |
59 |
Correct |
894 ms |
61548 KB |
Output is correct |
60 |
Correct |
821 ms |
60864 KB |
Output is correct |
61 |
Correct |
776 ms |
60712 KB |
Output is correct |
62 |
Correct |
904 ms |
61776 KB |
Output is correct |
63 |
Correct |
861 ms |
61268 KB |
Output is correct |
64 |
Execution timed out |
2065 ms |
68968 KB |
Time limit exceeded |
65 |
Halted |
0 ms |
0 KB |
- |