Submission #724369

# Submission time Handle Problem Language Result Execution time Memory
724369 2023-04-15T06:56:23 Z sunwukong123 Boat (APIO16_boat) C++14
27 / 100
2000 ms 15112 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(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;
				db3(j,k,dp[j][k]);
			}
		}
		
		memset(S,0,sizeof S);
		FOR(j,0,m-1){
			int val = 0;
			if(j==0){
				val=1;
			}
			FOR(k,1,min(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;
}



# Verdict Execution time Memory Grader output
1 Execution timed out 2086 ms 15112 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 2086 ms 15112 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 88 ms 2396 KB Output is correct
2 Correct 86 ms 2368 KB Output is correct
3 Correct 89 ms 2388 KB Output is correct
4 Correct 107 ms 2380 KB Output is correct
5 Correct 87 ms 2404 KB Output is correct
6 Correct 85 ms 2336 KB Output is correct
7 Correct 96 ms 2380 KB Output is correct
8 Correct 104 ms 2340 KB Output is correct
9 Correct 83 ms 2364 KB Output is correct
10 Correct 87 ms 2484 KB Output is correct
11 Correct 86 ms 2392 KB Output is correct
12 Correct 100 ms 2392 KB Output is correct
13 Correct 84 ms 2388 KB Output is correct
14 Correct 83 ms 2368 KB Output is correct
15 Correct 83 ms 2344 KB Output is correct
16 Correct 33 ms 1236 KB Output is correct
17 Correct 32 ms 1236 KB Output is correct
18 Correct 33 ms 1320 KB Output is correct
19 Correct 33 ms 1236 KB Output is correct
20 Correct 38 ms 1364 KB Output is correct
# Verdict Execution time Memory Grader output
1 Execution timed out 2086 ms 15112 KB Time limit exceeded
2 Halted 0 ms 0 KB -