# include <bits/stdc++.h>
using namespace std;
using ll = long long;
using db = long double; // or double, if TL is tight
using str = string; // yay python!
// pairs
using pii = pair<int,int>;
using pl = pair<ll,ll>;
using pd = pair<db,db>;
#define mp make_pair
#define f first
#define s second
#define tcT template<class T
#define tcTU tcT, class U
// ^ lol this makes everything look weird but I'll try it
tcT> using V = vector<T>;
tcT, size_t SZ> using AR = array<T,SZ>;
using vi = V<int>;
using vb = V<bool>;
using vl = V<ll>;
using vd = V<db>;
using vs = V<str>;
using vpi = V<pii>;
using vpl = V<pl>;
using vpd = V<pd>;
// vectors
// oops size(x), rbegin(x), rend(x) need C++17
#define sz(x) int((x).size())
#define bg(x) begin(x)
#define all(x) bg(x), end(x)
#define rall(x) x.rbegin(), x.rend()
#define sor(x) sort(all(x))
#define rsz resize
#define ins insert
#define pb push_back
#define eb emplace_back
#define ft front()
#define bk back()
#define lb lower_bound
#define ub upper_bound
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define rep(a) F0R(_,a)
#define each(a,x) for (auto& a: x)
const int MOD = 998244353;
const int MX = 2e5+5;
const ll BIG = 1e18; // not too close to LLONG_MAX
const db PI = acos((db)-1);
const int dx[4]{1,0,-1,0}, dy[4]{0,1,0,-1}; // for every grid problem!!
mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count());
template<class T> using pqg = priority_queue<T,vector<T>,greater<T>>;
struct DSU {
vi e; void init(int N) { e = vi(N,-1); }
int get(int x) { return e[x] < 0 ? x : e[x] = get(e[x]); }
bool sameSet(int a, int b) { return get(a) == get(b); }
int size(int x) { return -e[get(x)]; }
bool unite(int x, int y) { // union by size
x = get(x), y = get(y); if (x == y) return 0;
if (e[x] > e[y]) swap(x,y);
e[x] += e[y]; e[y] = x; return 1;
}
};
/*
inline namespace Helpers {
//////////// is_iterable
// https://stackoverflow.com/questions/13830158/check-if-a-variable-type-is-iterable
// this gets used only when we can call begin() and end() on that type
tcT, class = void> struct is_iterable : false_type {};
tcT> struct is_iterable<T, void_t<decltype(begin(declval<T>())),
decltype(end(declval<T>()))
>
> : true_type {};
tcT> constexpr bool is_iterable_v = is_iterable<T>::value;
//////////// is_readable
tcT, class = void> struct is_readable : false_type {};
tcT> struct is_readable<T,
typename std::enable_if_t<
is_same_v<decltype(cin >> declval<T&>()), istream&>
>
> : true_type {};
tcT> constexpr bool is_readable_v = is_readable<T>::value;
//////////// is_printable
// // https://nafe.es/posts/2020-02-29-is-printable/
tcT, class = void> struct is_printable : false_type {};
tcT> struct is_printable<T,
typename std::enable_if_t<
is_same_v<decltype(cout << declval<T>()), ostream&>
>
> : true_type {};
tcT> constexpr bool is_printable_v = is_printable<T>::value;
}*/
using ll = long long;
using db = long double; // or double, if TL is tight
using str = string; // yay python!
// pairs
using pii = pair<int,int>;
using pl = pair<ll,ll>;
using pd = pair<db,db>;
#define mp make_pair
#define f first
#define s second
#define tcT template<class T
#define tcTU tcT, class U
// ^ lol this makes everything look weird but I'll try it
tcT> using V = vector<T>;
tcT, size_t SZ> using AR = array<T,SZ>;
using vi = V<int>;
using vb = V<bool>;
using vl = V<ll>;
using vd = V<db>;
using vs = V<str>;
using vpi = V<pii>;
using vpl = V<pl>;
using vpd = V<pd>;
// vectors
// oops size(x), rbegin(x), rend(x) need C++17
#define sz(x) int((x).size())
#define bg(x) begin(x)
#define all(x) bg(x), end(x)
#define rall(x) x.rbegin(), x.rend()
#define sor(x) sort(all(x))
#define rsz resize
#define ins insert
#define pb push_back
#define eb emplace_back
#define ft front()
#define bk back()
#define lb lower_bound
#define ub upper_bound
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define rep(a) F0R(_,a)
#define each(a,x) for (auto& a: x)
template<class T> using pqg = priority_queue<T,vector<T>,greater<T>>;
/*
inline namespace Helpers {
//////////// is_iterable
// https://stackoverflow.com/questions/13830158/check-if-a-variable-type-is-iterable
// this gets used only when we can call begin() and end() on that type
tcT, class = void> struct is_iterable : false_type {};
tcT> struct is_iterable<T, void_t<decltype(begin(declval<T>())),
decltype(end(declval<T>()))
>
> : true_type {};
tcT> constexpr bool is_iterable_v = is_iterable<T>::value;
//////////// is_readable
tcT, class = void> struct is_readable : false_type {};
tcT> struct is_readable<T,
typename std::enable_if_t<
is_same_v<decltype(cin >> declval<T&>()), istream&>
>
> : true_type {};
tcT> constexpr bool is_readable_v = is_readable<T>::value;
//////////// is_printable
// // https://nafe.es/posts/2020-02-29-is-printable/
tcT, class = void> struct is_printable : false_type {};
tcT> struct is_printable<T,
typename std::enable_if_t<
is_same_v<decltype(cout << declval<T>()), ostream&>
>
> : true_type {};
tcT> constexpr bool is_printable_v = is_printable<T>::value;
}*/
#define int long long
const int N = 1005, mod = 1e9 + 7;
int t,n,a[N],b[N],pr[N][N],dp[N][N],inv[N],fq[N];
vector <int> v;
int f_p(int base, int power) {
int result = 1;
while (power > 0) {
if (power % 2) result = (result * base) % mod;
base = (base * base) % mod;
power /= 2;
}
return result;
}
int C(int n, int k) {
if (n < k) return 0;
if (n == 0 && k == 0) return 1;
int pas = 1;
for (int i = n; i >= n - k + 1; i--){
pas *= i;
pas %= mod;
}
pas *= inv[k];pas %= mod;
return pas;
}
int check(int le, int ri, int a, int b) {
return (max(a,le) <= min(b,ri));
}
main() {
ios_base::sync_with_stdio(false),
cin.tie(NULL),cout.tie(NULL);
cin>>n;
for (int i = 1; i <= n; i++) {
cin>>a[i]>>b[i];
v.pb(a[i]);
v.pb(b[i] + 1);
}
fq[0] = 1; inv[0] = 1;
for (int i = 1; i < N; i++) {
fq[i] = fq[i - 1] * i % mod;
}
inv[N - 1] = f_p(fq[N - 1], mod - 2);
for (int i = N - 2; i >= 1; i--) {
inv[i] = (inv[i + 1] * (i + 1)) % mod;
}
sort(v.begin(), v.end());
v.resize(unique(v.begin(), v.end())-v.begin());
vector <pii> seg;
seg.pb({-1,-1});
for (int i = 1; i < v.size(); i++) {
seg.pb({v[i - 1], v[i] - 1});
}
dp[0][0] = 1;
pr[0][0] = 1;
int ans = 0;
for (int i = 1; i < seg.size(); i++) pr[0][i] = 1;//, cout<<seg[i].f<<" "<<seg[i].s<<endl;
for (int i = 1; i <= n; i++) {
for (int j = 1; j < seg.size(); j++) {
int le = seg[j].f; int ri = seg[j].s;
if (check(le,ri,a[i],b[i])) {
int cnt = 1;
for (int prless = i - 1; prless >= 0; prless--) {
for (int cn = 1; cn <= cnt; cn++) {
//if ( i == 5 && j == 4) cout<<prless<<" --- > "<<pr[prless][j - 1] * C(ri - le + 1, cn) % mod<<endl;
dp[i][j] += (pr[prless][j - 1] * C(ri - le + 1, cn) % mod)* C(cnt-1,cn-1) % mod, dp[i][j] %= mod;
}
if ((check(le,ri,a[prless],b[prless]))) cnt++;
}
}
//if (dp[i][j]) cout<<i<<" "<<j<<" "<<dp[i][j]<<endl;
ans += dp[i][j]; ans %= mod;
pr[i][j] = (dp[i][j] + pr[i][j - 1]); pr[i][j] %= mod;
}
}
cout<<ans<<"\n";
}
Compilation message
boat.cpp:208:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
208 | main() {
| ^~~~
boat.cpp: In function 'int main()':
boat.cpp:230:20: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int, std::allocator<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
230 | for (int i = 1; i < v.size(); i++) {
| ~~^~~~~~~~~~
boat.cpp:236:20: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<int, int>, std::allocator<std::pair<int, int> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
236 | for (int i = 1; i < seg.size(); i++) pr[0][i] = 1;//, cout<<seg[i].f<<" "<<seg[i].s<<endl;
| ~~^~~~~~~~~~~~
boat.cpp:238:21: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<int, int>, std::allocator<std::pair<int, int> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
238 | for (int j = 1; j < seg.size(); j++) {
| ~~^~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
8 ms |
6228 KB |
Output is correct |
2 |
Correct |
9 ms |
6228 KB |
Output is correct |
3 |
Correct |
9 ms |
6228 KB |
Output is correct |
4 |
Correct |
11 ms |
6236 KB |
Output is correct |
5 |
Correct |
9 ms |
6228 KB |
Output is correct |
6 |
Correct |
9 ms |
6288 KB |
Output is correct |
7 |
Correct |
7 ms |
6228 KB |
Output is correct |
8 |
Correct |
8 ms |
6228 KB |
Output is correct |
9 |
Correct |
9 ms |
6228 KB |
Output is correct |
10 |
Correct |
11 ms |
6228 KB |
Output is correct |
11 |
Correct |
9 ms |
6228 KB |
Output is correct |
12 |
Correct |
11 ms |
6228 KB |
Output is correct |
13 |
Correct |
8 ms |
6228 KB |
Output is correct |
14 |
Correct |
9 ms |
6228 KB |
Output is correct |
15 |
Correct |
8 ms |
6328 KB |
Output is correct |
16 |
Correct |
9 ms |
5076 KB |
Output is correct |
17 |
Correct |
9 ms |
5104 KB |
Output is correct |
18 |
Correct |
9 ms |
5076 KB |
Output is correct |
19 |
Correct |
10 ms |
5092 KB |
Output is correct |
20 |
Correct |
10 ms |
5092 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
8 ms |
6228 KB |
Output is correct |
2 |
Correct |
9 ms |
6228 KB |
Output is correct |
3 |
Correct |
9 ms |
6228 KB |
Output is correct |
4 |
Correct |
11 ms |
6236 KB |
Output is correct |
5 |
Correct |
9 ms |
6228 KB |
Output is correct |
6 |
Correct |
9 ms |
6288 KB |
Output is correct |
7 |
Correct |
7 ms |
6228 KB |
Output is correct |
8 |
Correct |
8 ms |
6228 KB |
Output is correct |
9 |
Correct |
9 ms |
6228 KB |
Output is correct |
10 |
Correct |
11 ms |
6228 KB |
Output is correct |
11 |
Correct |
9 ms |
6228 KB |
Output is correct |
12 |
Correct |
11 ms |
6228 KB |
Output is correct |
13 |
Correct |
8 ms |
6228 KB |
Output is correct |
14 |
Correct |
9 ms |
6228 KB |
Output is correct |
15 |
Correct |
8 ms |
6328 KB |
Output is correct |
16 |
Correct |
9 ms |
5076 KB |
Output is correct |
17 |
Correct |
9 ms |
5104 KB |
Output is correct |
18 |
Correct |
9 ms |
5076 KB |
Output is correct |
19 |
Correct |
10 ms |
5092 KB |
Output is correct |
20 |
Correct |
10 ms |
5092 KB |
Output is correct |
21 |
Execution timed out |
2082 ms |
2156 KB |
Time limit exceeded |
22 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
386 ms |
1452 KB |
Output is correct |
2 |
Correct |
217 ms |
1324 KB |
Output is correct |
3 |
Correct |
327 ms |
1356 KB |
Output is correct |
4 |
Correct |
399 ms |
1432 KB |
Output is correct |
5 |
Correct |
485 ms |
1356 KB |
Output is correct |
6 |
Correct |
1883 ms |
1428 KB |
Output is correct |
7 |
Correct |
1875 ms |
1492 KB |
Output is correct |
8 |
Correct |
1876 ms |
1584 KB |
Output is correct |
9 |
Correct |
1923 ms |
1672 KB |
Output is correct |
10 |
Correct |
1903 ms |
1444 KB |
Output is correct |
11 |
Correct |
463 ms |
1300 KB |
Output is correct |
12 |
Correct |
230 ms |
1356 KB |
Output is correct |
13 |
Correct |
300 ms |
1320 KB |
Output is correct |
14 |
Correct |
307 ms |
1344 KB |
Output is correct |
15 |
Correct |
454 ms |
1388 KB |
Output is correct |
16 |
Correct |
229 ms |
1228 KB |
Output is correct |
17 |
Correct |
163 ms |
1344 KB |
Output is correct |
18 |
Correct |
204 ms |
1216 KB |
Output is correct |
19 |
Correct |
164 ms |
1264 KB |
Output is correct |
20 |
Correct |
267 ms |
1352 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
8 ms |
6228 KB |
Output is correct |
2 |
Correct |
9 ms |
6228 KB |
Output is correct |
3 |
Correct |
9 ms |
6228 KB |
Output is correct |
4 |
Correct |
11 ms |
6236 KB |
Output is correct |
5 |
Correct |
9 ms |
6228 KB |
Output is correct |
6 |
Correct |
9 ms |
6288 KB |
Output is correct |
7 |
Correct |
7 ms |
6228 KB |
Output is correct |
8 |
Correct |
8 ms |
6228 KB |
Output is correct |
9 |
Correct |
9 ms |
6228 KB |
Output is correct |
10 |
Correct |
11 ms |
6228 KB |
Output is correct |
11 |
Correct |
9 ms |
6228 KB |
Output is correct |
12 |
Correct |
11 ms |
6228 KB |
Output is correct |
13 |
Correct |
8 ms |
6228 KB |
Output is correct |
14 |
Correct |
9 ms |
6228 KB |
Output is correct |
15 |
Correct |
8 ms |
6328 KB |
Output is correct |
16 |
Correct |
9 ms |
5076 KB |
Output is correct |
17 |
Correct |
9 ms |
5104 KB |
Output is correct |
18 |
Correct |
9 ms |
5076 KB |
Output is correct |
19 |
Correct |
10 ms |
5092 KB |
Output is correct |
20 |
Correct |
10 ms |
5092 KB |
Output is correct |
21 |
Execution timed out |
2082 ms |
2156 KB |
Time limit exceeded |
22 |
Halted |
0 ms |
0 KB |
- |