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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#792150#9280. New Randomized Gobulijiojiodibuliduo#WA 3ms13792kbC++174.2kb2024-11-29 01:31:402024-11-29 01:31:40

Judging History

你现在查看的是最新测评结果

  • [2024-11-29 01:31:40]
  • 评测
  • 测评结果:WA
  • 用时:3ms
  • 内存:13792kb
  • [2024-11-29 01:31:40]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef basic_string<int> BI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
mt19937 mrand(random_device{}()); 
const ll mod=1000000007;
int rnd(int x) { return mrand() % x;}
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head

template<int MOD, int RT> struct mint {
	static const int mod = MOD;
	static constexpr mint rt() { return RT; } // primitive root for FFT
	int v; explicit operator int() const { return v; } // explicit -> don't silently convert to int
	mint():v(0) {}
	mint(ll _v) { v = int((-MOD < _v && _v < MOD) ? _v : _v % MOD);
		if (v < 0) v += MOD; }
	bool operator==(const mint& o) const {
		return v == o.v; }
	friend bool operator!=(const mint& a, const mint& b) { 
		return !(a == b); }
	friend bool operator<(const mint& a, const mint& b) { 
		return a.v < b.v; }
   
	mint& operator+=(const mint& o) { 
		if ((v += o.v) >= MOD) v -= MOD; 
		return *this; }
	mint& operator-=(const mint& o) { 
		if ((v -= o.v) < 0) v += MOD; 
		return *this; }
	mint& operator*=(const mint& o) { 
		v = int((ll)v*o.v%MOD); return *this; }
	mint& operator/=(const mint& o) { return (*this) *= inv(o); }
	friend mint pow(mint a, ll p) {
		mint ans = 1; assert(p >= 0);
		for (; p; p /= 2, a *= a) if (p&1) ans *= a;
		return ans; }
	friend mint inv(const mint& a) { assert(a.v != 0); 
		return pow(a,MOD-2); }
		
	mint operator-() const { return mint(-v); }
	mint& operator++() { return *this += 1; }
	mint& operator--() { return *this -= 1; }
	friend mint operator+(mint a, const mint& b) { return a += b; }
	friend mint operator-(mint a, const mint& b) { return a -= b; }
	friend mint operator*(mint a, const mint& b) { return a *= b; }
	friend mint operator/(mint a, const mint& b) { return a /= b; }
};

const int MOD=1000000007; 
using mi = mint<MOD,5>; // 5 is primitive root for both common mods

namespace simp {
	vector<mi> fac,ifac,invn;
	void check(int x) {
		if (fac.empty()) {
			fac={mi(1),mi(1)};
			ifac={mi(1),mi(1)};
			invn={mi(0),mi(1)};
		}
		while (SZ(fac)<=x) {
			int n=SZ(fac),m=SZ(fac)*2;
			fac.resize(m);
			ifac.resize(m);
			invn.resize(m);
			for (int i=n;i<m;i++) {
				fac[i]=fac[i-1]*mi(i);
				invn[i]=mi(MOD-MOD/i)*invn[MOD%i];
				ifac[i]=ifac[i-1]*invn[i];
			}
		}
	}
	mi gfac(int x) {
		assert(x>=0);
		check(x); return fac[x];
	}
	mi ginv(int x) {
		assert(x>0);
		check(x); return invn[x];
	}
	mi gifac(int x) {
		assert(x>=0);
		check(x); return ifac[x];
	}
	mi binom(int n,int m) {
		if (m < 0 || m > n) return mi(0);
		return gfac(n)*gifac(m)*gifac(n - m);
	}
	mi binombf(int n,int m) {
		if (m < 0 || m > n) return mi(0);
		if (m>n-m) m=n-m;
		mi p=1,q=1;
		for (int i=1;i<=m;i++) p=p*(n+1-i),q=q*i;
		return p/q;
	}
}


const int N=2010000;

int n;
ll l,x[N];
mi pw[N];
mi single() {
	mi ans=0;
	ans+=1;
	int r=0;
	rep(i,0,n) {
		while (x[r]<x[i]+l) r++;
		//printf("%d %d\n",i,r);
		ans+=pw[r-i-1];
	}
	//printf("? %d\n",(int)ans);
	return ans;
}
int cnt(int l,int r) {
	//assert(l>=0&&r<4*::l);
	int cc=lower_bound(x,x+2*n,r+1)-lower_bound(x,x+2*n,l);
	//rep(i,0,2*n) cc+=x[i]>=l&&x[i]<=r;
	//printf("?? %d %d %d\n",l,r,cc);
	return cc;
}
mi dbl() {
	mi ans=0;
	int r=0;
	rep(i,0,n) {
		while (x[r]<x[i]+l) r++;
		assert(r<=i+n-1);
		// r .. i+n-1 ->R
		ans+=1;
		ans+=pw[cnt(x[i+n-1]-l+1,x[r]-1)]-1;
		ans+=pw[cnt(x[i+n-1]+1,x[r]+l-1)-(x[i+n]<x[r]+l)]-1;
	}
	return ans;
}
int main() {
	scanf("%d%lld",&n,&l);
	pw[0]=1;
	rep(i,1,n+1) pw[i]=pw[i-1]*2;
	rep(i,0,n) {
		scanf("%lld",&x[i]);
		x[i]=x[i]*2;
	}
	sort(x,x+n);
	rep(i,0,n) x[i+n]=x[i]+2*l;
	rep(i,0,n) if (x[i+n-1]-x[i]<l) {
		puts("0");
		return 0;
	}
	mi pr=pw[n]-2*single()+dbl();
	pr/=pw[n];
	printf("%d\n",(int)pr);
}

详细

Test #1:

score: 100
Accepted
time: 2ms
memory: 12188kb

input:

4 100
0 30 50 80

output:

125000001

result:

ok 1 number(s): "125000001"

Test #2:

score: 0
Accepted
time: 0ms
memory: 12836kb

input:

8 100
1 12 34 45 51 84 88 92

output:

515625004

result:

ok 1 number(s): "515625004"

Test #3:

score: 0
Accepted
time: 0ms
memory: 12080kb

input:

6 123
1 21 41 61 81 101

output:

562500004

result:

ok 1 number(s): "562500004"

Test #4:

score: 0
Accepted
time: 0ms
memory: 12148kb

input:

1 1000
999

output:

0

result:

ok 1 number(s): "0"

Test #5:

score: 0
Accepted
time: 0ms
memory: 12328kb

input:

2 999
123 456

output:

0

result:

ok 1 number(s): "0"

Test #6:

score: 0
Accepted
time: 2ms
memory: 12332kb

input:

3 400
100 200 300

output:

0

result:

ok 1 number(s): "0"

Test #7:

score: 0
Accepted
time: 2ms
memory: 12764kb

input:

4 500
100 200 300 401

output:

0

result:

ok 1 number(s): "0"

Test #8:

score: 0
Accepted
time: 0ms
memory: 12096kb

input:

5 600
100 200 300 400 500

output:

125000001

result:

ok 1 number(s): "125000001"

Test #9:

score: 0
Accepted
time: 2ms
memory: 12400kb

input:

5 599
100 200 300 400 500

output:

0

result:

ok 1 number(s): "0"

Test #10:

score: 0
Accepted
time: 0ms
memory: 13792kb

input:

5 600
100 200 300 400 501

output:

562500004

result:

ok 1 number(s): "562500004"

Test #11:

score: 0
Accepted
time: 3ms
memory: 13620kb

input:

6 311
2 25 87 117 251 269

output:

0

result:

ok 1 number(s): "0"

Test #12:

score: 0
Accepted
time: 0ms
memory: 13400kb

input:

10 49
0 7 12 13 17 19 22 28 30 38

output:

527343754

result:

ok 1 number(s): "527343754"

Test #13:

score: 0
Accepted
time: 0ms
memory: 11716kb

input:

11 39
0 1 9 15 19 21 23 25 28 37 38

output:

62500001

result:

ok 1 number(s): "62500001"

Test #14:

score: 0
Accepted
time: 3ms
memory: 13436kb

input:

12 39
10 12 15 16 20 23 24 25 26 30 31 38

output:

596679692

result:

ok 1 number(s): "596679692"

Test #15:

score: 0
Accepted
time: 3ms
memory: 12992kb

input:

12 100
25 26 29 33 36 45 46 51 53 63 72 74

output:

0

result:

ok 1 number(s): "0"

Test #16:

score: 0
Accepted
time: 2ms
memory: 11976kb

input:

13 100
0 1 3 4 5 10 15 19 21 36 40 44 48

output:

0

result:

ok 1 number(s): "0"

Test #17:

score: 0
Accepted
time: 0ms
memory: 13448kb

input:

13 100
50 53 55 61 72 78 79 84 86 89 96 97 98

output:

0

result:

ok 1 number(s): "0"

Test #18:

score: -100
Wrong Answer
time: 0ms
memory: 12988kb

input:

14 100
20 22 24 26 29 35 39 88 91 93 96 97 98 99

output:

378356936

result:

wrong answer 1st numbers differ - expected: '0', found: '378356936'