oj.uz

Submission #724371

# Submission time Handle Problem Language Result Execution time Memory
724371 2023-04-15T06:59:07 Z sunwukong123 Boat (APIO16_boat) C++14
27 / 100
 2000 ms 10916 KB 
#include <bits/stdc++.h>
using namespace std;
#define int long long 
#define FOR(i,s,e) for(int i = s; i <= (int)e; ++i)
#define DEC(i,s,e) for(int i = s; i >= (int)e; --i)
#define IAMSPEED ios_base::sync_with_stdio(false); cin.tie(0);
#ifdef LOCAL
#define db(x) cerr << #x << "=" << x << "\n"
#define db2(x, y) cerr << #x << "=" << x << " , " << #y << "=" << y << "\n"
#define db3(a,b,c) cerr<<#a<<"="<<a<<","<<#b<<"="<<b<<","<<#c<<"="<<c<<"\n"
#define dbv(v) cerr << #v << ":"; for (auto ite : v) cerr << ite << ' '; cerr <<"\n"
#define dbvp(v) cerr << #v << ":"; for (auto ite : v) cerr << "{"  << ite.f << ',' << ite.s << "} "; cerr << "\n"
#define dba(a,ss,ee) cerr << #a << ":"; FOR(ite,ss,ee) cerr << a[ite] << ' '; cerr << "\n"
#define reach cerr << "LINE: " << __LINE__ << "\n";
#else
#define reach 
#define db(x)
#define db2(x,y)
#define db3(a,b,c)
#define dbv(v)
#define dbvp(v)
#define dba(a,ss,ee)
#endif
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define pb push_back
#define eb emplace_back
#define all(x) (x).begin(), (x).end()
#define f first 
#define s second
#define g0(x) get<0>(x)
#define g1(x) get<1>(x)
#define g2(x) get<2>(x)
#define g3(x) get<3>(x)
typedef pair <int, int> pi;
typedef tuple<int,int,int> ti3;
typedef tuple<int,int,int,int> ti4;
int rand(int a, int b) { return a + rng() % (b-a+1); }
const int MOD = 1e9 + 7;
const int inf = (int)1e9 + 500;
const long long oo = (long long)1e18 + 500;
template <typename T> void chmax(T& a, const T b) { a=max(a,b); }
template <typename T> void chmin(T& a, const T b) { a=min(a,b); }
const int MAXN = 1005;
int n;
vector<int> points;
int L[MAXN],R[MAXN];
int dp[MAXN][MAXN]; // dp(i,c)=number of ways to reach the ith segment with c objects inside the ith segment
int S[MAXN];
int sz[MAXN];
int qexp(int a, int b, int mod) {
	a%=mod;
	int res = 1;
	while(b) {
		if(b&1)res=res*a%mod;
		a=a*a%mod;
		b>>=1;
	}
	return res;
}
struct hash_pair {
    static uint64_t splitmix64(uint64_t x) {
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }
    size_t operator()(pair<uint64_t,uint64_t> x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x.first + FIXED_RANDOM)^(splitmix64(x.second + FIXED_RANDOM) >> 1);
    }
};

unordered_map<pi,int,hash_pair>memo;
int choose(int n, int k) {
	auto it=memo.find({n,k});
	if(it!=memo.end())return it->s;
    int x = 1, y = 1;
    FOR(i,0,k-1) {
        y*=n-i;
        x*=k-i;
        y%=MOD;
        x%=MOD;
    }
    return memo[{n,k}]=(y*qexp(x,MOD-2,MOD)) % MOD;
}
int32_t main() 
{
	IAMSPEED
	
	cin >> n;
	FOR(i,1,n){
		cin >> L[i] >> R[i];
		points.pb(L[i]);
		points.pb(R[i]+1);
	}
	points.pb(-inf);
	sort(all(points)); 
	points.resize(unique(all(points))-points.begin());

	// my ith segment is points[i] to points[i+1]
	int m=points.size();
	FOR(i,0,m-2)sz[i]=points[i+1]-points[i];
	FOR(i,0,m-1)S[i]=1;
	FOR(i,1,n) {

		int ls=lower_bound(all(points),L[i])-points.begin();
		int rs=lower_bound(all(points),R[i]+1)-points.begin();

		DEC(j,rs-1,ls){
			DEC(k,min({i,sz[j],n}),1){ 
				if(k>1)dp[j][k]=(dp[j][k]+dp[j][k-1])%MOD;
				else if(j)dp[j][k]=(dp[j][k]+S[j-1])%MOD;
			}
		}
		
		memset(S,0,sizeof S);
		FOR(j,0,m-1){
			int val = 0;
			if(j==0){
				val=1;
			}
			FOR(k,1,min({i,n,sz[j]})){
				val=(val+dp[j][k]*choose(sz[j],k)%MOD)%MOD;
			}
			if(j)S[j]=(S[j-1]+val)%MOD;
			else S[j]=1;
		}
	}
	cout<<(S[m-1]-1+MOD)%MOD;
}

Subtask #1
0 / 9.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2070 ms 10916 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #2
0 / 22.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2070 ms 10916 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #3
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 61 ms 2316 KB Output is correct
2 Correct 74 ms 2388 KB Output is correct
3 Correct 55 ms 2356 KB Output is correct
4 Correct 51 ms 2304 KB Output is correct
5 Correct 50 ms 2380 KB Output is correct
6 Correct 74 ms 2300 KB Output is correct
7 Correct 55 ms 2304 KB Output is correct
8 Correct 64 ms 2380 KB Output is correct
9 Correct 51 ms 2316 KB Output is correct
10 Correct 55 ms 2292 KB Output is correct
11 Correct 51 ms 2312 KB Output is correct
12 Correct 53 ms 2340 KB Output is correct
13 Correct 51 ms 2284 KB Output is correct
14 Correct 50 ms 2352 KB Output is correct
15 Correct 61 ms 2336 KB Output is correct
16 Correct 20 ms 1236 KB Output is correct
17 Correct 22 ms 1296 KB Output is correct
18 Correct 20 ms 1236 KB Output is correct
19 Correct 20 ms 1356 KB Output is correct
20 Correct 21 ms 1276 KB Output is correct

Subtask #4
0 / 42.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2070 ms 10916 KB Time limit exceeded
2 Halted 0 ms 0 KB -