#include <bits/stdc++.h>
#define f first
#define s second
#define m_p make_pair
#define pb push_back
#define vec vector
#define sz(x) (int)(x).size()
#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()
#define pw(x) (1LL<<(x))
#define fast_iati ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
using namespace std;
template<class T> bool umin(T &a,const T &b){return (a>b?a=b,1:0);}
template<class T> bool umax(T &a,const T &b){return (a<b?a=b,1:0);}
typedef long long ll;
typedef pair<int,int> pii;
const int M=1e9+7;
const int N=5e2+10;
const int Mx=200+1;
void add(int &a,int b){
a+=b;
if(a>=M) a-=M;
else if(a<0) a+=M;
}
int mult(int a,int b){
return 1ll*a*b%M;
}
int binpow(int a,int b){
int ans=1;
while(b){
if(b&1) ans=mult(ans,a);
b>>=1;a=mult(a,a);
}
return ans;
}
int inv[N];
int gi(int x){
if(!inv[x]) inv[x]=binpow(x,M-2);
return inv[x];
}
int C(int k,int n){
if(k>n) return 0;
int ans=1;
for(int i=n-k+1;i<=n;i++) ans=mult(ans,i);
for(int i=1;i<=k;i++) ans=mult(ans,gi(i));
return ans;
}
signed main(){
fast_iati;
int tests=1;
while(tests--){
int n=200;
cin>>n;
vec<int>a(n),b(n);
vec<int> kek;
for(int i=0;i<n;i++) {
cin>>a[i]>>b[i];
// a[i]=rand()%Mx+1,b[i]=rand()%Mx+1;
// if(a[i]>b[i]) swap(a[i],b[i]);
kek.pb(a[i]-1),kek.pb(b[i]);
}
vec<int>l,r;l=a;r=b;
auto solve=[&](){
kek.pb(0);sort(all(kek));kek.erase(unique(all(kek)),kek.end());
vec<vec<int>>dp(n+1,vec<int>(sz(kek)+1,0));
vec<vec<int>>pref(n+1,vec<int>(sz(kek)+1,0));
vec<int>ways(sz(kek));
vec<vec<int>>col(sz(kek),vec<int>(n+1,0));
vec<vec<int>>cnk(n+1,vec<int>(n+1,0));
cnk[0][0]=1;
for(int i=1;i<=n;i++){
for(int j=0;j<=i;j++){
cnk[i][j]=cnk[i-1][j];
if(j)
add(cnk[i][j],cnk[i-1][j-1]);
}
}
for(int i=1;i<sz(kek);i++){
ways[i]=kek[i]-kek[i-1];
vec<int> ct(n+1,0);
ct[0]=1;
for(int j=1;j<=n;j++){
if(j>ways[i]) ct[j]=0;
else{
ct[j]=mult(ct[j-1],ways[i]-j+1);
ct[j]=mult(ct[j],gi(j));
}
// cout<<"DEBUGFGEEGEGE"<<"C "<<j<<' '<<ways[i]<<' '<<ct[j]<<' '<<endl;
}
/// so
col[i][2]=ct[2];
// cout<<ct[2]<<endl;
// cout<<endl;
// cout<<"YEA "<<ways[]
for(int j=3;j<=n;j++){
// col[i][j]=col[i][j-1];
// col[i][j]=mult(col[i][j],j-2);
// add(col[i][j],ct[j]);
int fuck=0;
for(int t=2;t<=j;t++){
add(col[i][j],mult(ct[t],cnk[j-2][t-2]));
// cout<<"SHE "<<mult(C(t,ways[i]),C(t-2,j-2))<<endl;
}
// cout<<"DEBIL "<<ways[i]<<' '<<j<<' '<<col[i][j]<<' '<<fuck<<endl;
}
// cout<<endl;
}
for(int j=0;j<sz(kek);j++) pref[0][j]=1;
for(int i=0;i<n;i++){
a[i]=lower_bound(all(kek),a[i]-1)-kek.begin()+1;
b[i]=lower_bound(all(kek),b[i])-kek.begin();
}
for(int i=0;i<n;i++){
for(int j=a[i];j<=b[i];j++){
/// I start with me
/// then it's pref[i][j-1]
add(dp[i+1][j],mult(ways[j],pref[i][j-1]));
// if(i==1)cout<<"ALO "<<pref[i][j-1]<<endl;
if(ways[j]>=2){
int cnt=1;
for(int k=i-1;k>=0;k--){
if(a[k]>j || b[k]<j) continue;
cnt++;
// cout<<"CHECK "<<i<<' '<<k<<' '<<j<<' '<<' '<<col[j][cnt]<<' '<<pref[k][j-1]<<endl;
add(dp[i+1][j],mult(col[j][cnt],pref[k][j-1]));
}
}
}
// for(int j=0;j<sz(kek);j++){
// cout<<"DEBUG "<<(j?kek[j-1]+1:0)<<' '<<kek[j]<<' '<<dp[i+1][j]<<endl;
// }
// cout<<endl;
for(int j=0;j<sz(kek);j++){
pref[i+1][j]=dp[i+1][j];
if(j)add(pref[i+1][j],pref[i+1][j-1]);
}
for(int j=0;j<sz(kek);j++){
add(pref[i+1][j],pref[i][j]);
}
}
return pref[n][sz(kek)-1];
};
auto stupid=[&](){
vec<vec<int>>dp1(n+1,vec<int>(Mx+1,0));
for(int j=0;j<=Mx;j++) dp1[0][j]=1;
for(int i=0;i<n;i++){
// cout<<"AUE "<<l[i]<<' '<<r[i]<<endl;
for(int x=l[i];x<=r[i];x++){
add(dp1[i+1][x],dp1[i][x-1]);
}
for(int j=1;j<=Mx;j++)add(dp1[i+1][j],dp1[i+1][j-1]);
// cout<<endl;
for(int j=0;j<=Mx;j++){
add(dp1[i+1][j],dp1[i][j]);
}
}
return dp1[n][Mx];
};
int rans=solve();
add(rans,-1);
cout<<rans;
// cout<<"SOL "<<stupid()<<' '<<solve()<<endl;
// int x=solve(),y=stupid();
// if(x!=y){
// cout<<y<<' '<<x<<endl;
// cout<<n<<endl;
// for(int i=0;i<n;i++) cout<<l[i]<<' '<<r[i]<<endl;
// return 0;
// }
}
return 0;
}
Compilation message
boat.cpp: In lambda function:
boat.cpp:102:25: warning: unused variable 'fuck' [-Wunused-variable]
102 | int fuck=0;
| ^~~~
boat.cpp: In function 'int main()':
boat.cpp:147:14: warning: variable 'stupid' set but not used [-Wunused-but-set-variable]
147 | auto stupid=[&](){
| ^~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
746 ms |
7276 KB |
Output is correct |
2 |
Correct |
771 ms |
7272 KB |
Output is correct |
3 |
Correct |
792 ms |
7268 KB |
Output is correct |
4 |
Correct |
727 ms |
7268 KB |
Output is correct |
5 |
Correct |
790 ms |
7276 KB |
Output is correct |
6 |
Correct |
721 ms |
7276 KB |
Output is correct |
7 |
Correct |
751 ms |
7272 KB |
Output is correct |
8 |
Correct |
701 ms |
7272 KB |
Output is correct |
9 |
Correct |
716 ms |
7272 KB |
Output is correct |
10 |
Correct |
720 ms |
7364 KB |
Output is correct |
11 |
Correct |
735 ms |
7276 KB |
Output is correct |
12 |
Correct |
775 ms |
7276 KB |
Output is correct |
13 |
Correct |
729 ms |
7272 KB |
Output is correct |
14 |
Correct |
772 ms |
7276 KB |
Output is correct |
15 |
Correct |
736 ms |
7272 KB |
Output is correct |
16 |
Correct |
131 ms |
2420 KB |
Output is correct |
17 |
Correct |
144 ms |
2508 KB |
Output is correct |
18 |
Correct |
128 ms |
2380 KB |
Output is correct |
19 |
Correct |
136 ms |
2484 KB |
Output is correct |
20 |
Correct |
141 ms |
2440 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
746 ms |
7276 KB |
Output is correct |
2 |
Correct |
771 ms |
7272 KB |
Output is correct |
3 |
Correct |
792 ms |
7268 KB |
Output is correct |
4 |
Correct |
727 ms |
7268 KB |
Output is correct |
5 |
Correct |
790 ms |
7276 KB |
Output is correct |
6 |
Correct |
721 ms |
7276 KB |
Output is correct |
7 |
Correct |
751 ms |
7272 KB |
Output is correct |
8 |
Correct |
701 ms |
7272 KB |
Output is correct |
9 |
Correct |
716 ms |
7272 KB |
Output is correct |
10 |
Correct |
720 ms |
7364 KB |
Output is correct |
11 |
Correct |
735 ms |
7276 KB |
Output is correct |
12 |
Correct |
775 ms |
7276 KB |
Output is correct |
13 |
Correct |
729 ms |
7272 KB |
Output is correct |
14 |
Correct |
772 ms |
7276 KB |
Output is correct |
15 |
Correct |
736 ms |
7272 KB |
Output is correct |
16 |
Correct |
131 ms |
2420 KB |
Output is correct |
17 |
Correct |
144 ms |
2508 KB |
Output is correct |
18 |
Correct |
128 ms |
2380 KB |
Output is correct |
19 |
Correct |
136 ms |
2484 KB |
Output is correct |
20 |
Correct |
141 ms |
2440 KB |
Output is correct |
21 |
Correct |
679 ms |
6748 KB |
Output is correct |
22 |
Correct |
674 ms |
6836 KB |
Output is correct |
23 |
Correct |
632 ms |
6736 KB |
Output is correct |
24 |
Correct |
663 ms |
6696 KB |
Output is correct |
25 |
Correct |
654 ms |
6720 KB |
Output is correct |
26 |
Correct |
673 ms |
6576 KB |
Output is correct |
27 |
Correct |
670 ms |
6672 KB |
Output is correct |
28 |
Correct |
692 ms |
6572 KB |
Output is correct |
29 |
Correct |
687 ms |
6544 KB |
Output is correct |
30 |
Correct |
703 ms |
7288 KB |
Output is correct |
31 |
Correct |
707 ms |
7288 KB |
Output is correct |
32 |
Correct |
702 ms |
7284 KB |
Output is correct |
33 |
Correct |
733 ms |
7284 KB |
Output is correct |
34 |
Correct |
741 ms |
7260 KB |
Output is correct |
35 |
Correct |
699 ms |
7248 KB |
Output is correct |
36 |
Correct |
715 ms |
7196 KB |
Output is correct |
37 |
Correct |
690 ms |
7280 KB |
Output is correct |
38 |
Correct |
683 ms |
7248 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
11 ms |
616 KB |
Output is correct |
2 |
Correct |
26 ms |
620 KB |
Output is correct |
3 |
Correct |
10 ms |
616 KB |
Output is correct |
4 |
Correct |
11 ms |
616 KB |
Output is correct |
5 |
Correct |
11 ms |
592 KB |
Output is correct |
6 |
Correct |
14 ms |
604 KB |
Output is correct |
7 |
Correct |
13 ms |
620 KB |
Output is correct |
8 |
Correct |
12 ms |
624 KB |
Output is correct |
9 |
Correct |
13 ms |
624 KB |
Output is correct |
10 |
Correct |
13 ms |
620 KB |
Output is correct |
11 |
Correct |
13 ms |
636 KB |
Output is correct |
12 |
Correct |
12 ms |
620 KB |
Output is correct |
13 |
Correct |
12 ms |
620 KB |
Output is correct |
14 |
Correct |
11 ms |
620 KB |
Output is correct |
15 |
Correct |
13 ms |
616 KB |
Output is correct |
16 |
Correct |
7 ms |
464 KB |
Output is correct |
17 |
Correct |
6 ms |
464 KB |
Output is correct |
18 |
Correct |
6 ms |
512 KB |
Output is correct |
19 |
Correct |
6 ms |
464 KB |
Output is correct |
20 |
Correct |
6 ms |
508 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
746 ms |
7276 KB |
Output is correct |
2 |
Correct |
771 ms |
7272 KB |
Output is correct |
3 |
Correct |
792 ms |
7268 KB |
Output is correct |
4 |
Correct |
727 ms |
7268 KB |
Output is correct |
5 |
Correct |
790 ms |
7276 KB |
Output is correct |
6 |
Correct |
721 ms |
7276 KB |
Output is correct |
7 |
Correct |
751 ms |
7272 KB |
Output is correct |
8 |
Correct |
701 ms |
7272 KB |
Output is correct |
9 |
Correct |
716 ms |
7272 KB |
Output is correct |
10 |
Correct |
720 ms |
7364 KB |
Output is correct |
11 |
Correct |
735 ms |
7276 KB |
Output is correct |
12 |
Correct |
775 ms |
7276 KB |
Output is correct |
13 |
Correct |
729 ms |
7272 KB |
Output is correct |
14 |
Correct |
772 ms |
7276 KB |
Output is correct |
15 |
Correct |
736 ms |
7272 KB |
Output is correct |
16 |
Correct |
131 ms |
2420 KB |
Output is correct |
17 |
Correct |
144 ms |
2508 KB |
Output is correct |
18 |
Correct |
128 ms |
2380 KB |
Output is correct |
19 |
Correct |
136 ms |
2484 KB |
Output is correct |
20 |
Correct |
141 ms |
2440 KB |
Output is correct |
21 |
Correct |
679 ms |
6748 KB |
Output is correct |
22 |
Correct |
674 ms |
6836 KB |
Output is correct |
23 |
Correct |
632 ms |
6736 KB |
Output is correct |
24 |
Correct |
663 ms |
6696 KB |
Output is correct |
25 |
Correct |
654 ms |
6720 KB |
Output is correct |
26 |
Correct |
673 ms |
6576 KB |
Output is correct |
27 |
Correct |
670 ms |
6672 KB |
Output is correct |
28 |
Correct |
692 ms |
6572 KB |
Output is correct |
29 |
Correct |
687 ms |
6544 KB |
Output is correct |
30 |
Correct |
703 ms |
7288 KB |
Output is correct |
31 |
Correct |
707 ms |
7288 KB |
Output is correct |
32 |
Correct |
702 ms |
7284 KB |
Output is correct |
33 |
Correct |
733 ms |
7284 KB |
Output is correct |
34 |
Correct |
741 ms |
7260 KB |
Output is correct |
35 |
Correct |
699 ms |
7248 KB |
Output is correct |
36 |
Correct |
715 ms |
7196 KB |
Output is correct |
37 |
Correct |
690 ms |
7280 KB |
Output is correct |
38 |
Correct |
683 ms |
7248 KB |
Output is correct |
39 |
Correct |
11 ms |
616 KB |
Output is correct |
40 |
Correct |
26 ms |
620 KB |
Output is correct |
41 |
Correct |
10 ms |
616 KB |
Output is correct |
42 |
Correct |
11 ms |
616 KB |
Output is correct |
43 |
Correct |
11 ms |
592 KB |
Output is correct |
44 |
Correct |
14 ms |
604 KB |
Output is correct |
45 |
Correct |
13 ms |
620 KB |
Output is correct |
46 |
Correct |
12 ms |
624 KB |
Output is correct |
47 |
Correct |
13 ms |
624 KB |
Output is correct |
48 |
Correct |
13 ms |
620 KB |
Output is correct |
49 |
Correct |
13 ms |
636 KB |
Output is correct |
50 |
Correct |
12 ms |
620 KB |
Output is correct |
51 |
Correct |
12 ms |
620 KB |
Output is correct |
52 |
Correct |
11 ms |
620 KB |
Output is correct |
53 |
Correct |
13 ms |
616 KB |
Output is correct |
54 |
Correct |
7 ms |
464 KB |
Output is correct |
55 |
Correct |
6 ms |
464 KB |
Output is correct |
56 |
Correct |
6 ms |
512 KB |
Output is correct |
57 |
Correct |
6 ms |
464 KB |
Output is correct |
58 |
Correct |
6 ms |
508 KB |
Output is correct |
59 |
Correct |
1347 ms |
7288 KB |
Output is correct |
60 |
Correct |
1275 ms |
7284 KB |
Output is correct |
61 |
Correct |
1268 ms |
7304 KB |
Output is correct |
62 |
Correct |
1326 ms |
7284 KB |
Output is correct |
63 |
Correct |
1256 ms |
7284 KB |
Output is correct |
64 |
Correct |
1357 ms |
7292 KB |
Output is correct |
65 |
Correct |
1427 ms |
7284 KB |
Output is correct |
66 |
Correct |
1402 ms |
7288 KB |
Output is correct |
67 |
Correct |
1384 ms |
7292 KB |
Output is correct |
68 |
Correct |
1336 ms |
7292 KB |
Output is correct |
69 |
Correct |
1206 ms |
7288 KB |
Output is correct |
70 |
Correct |
1176 ms |
7288 KB |
Output is correct |
71 |
Correct |
1196 ms |
7284 KB |
Output is correct |
72 |
Correct |
1304 ms |
7280 KB |
Output is correct |
73 |
Correct |
1143 ms |
7248 KB |
Output is correct |
74 |
Correct |
161 ms |
2440 KB |
Output is correct |
75 |
Correct |
162 ms |
2480 KB |
Output is correct |
76 |
Correct |
161 ms |
2504 KB |
Output is correct |
77 |
Correct |
167 ms |
2448 KB |
Output is correct |
78 |
Correct |
168 ms |
2432 KB |
Output is correct |