#include <bits/stdc++.h>
using namespace std;
// macros
typedef long long ll;
typedef long double ld;
typedef pair<int, int> ii;
typedef pair<ll, ll> lll;
typedef tuple<int, int, int> iii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<iii> viii;
typedef vector<ll> vll;
typedef vector<lll> vlll;
#define REP(a,b,c) for(int a=int(b); a<int(c); a++)
#define RE(a,c) REP(a,0,c)
#define RE1(a,c) REP(a,1,c+1)
#define REI(a,b,c) REP(a,b,c+1)
#define REV(a,b,c) for(int a=int(c-1); a>=int(b); a--)
#define FOR(a,b) for(auto& a : b)
#define all(a) a.begin(), a.end()
#define INF 1e9
#define EPS 1e-9
#define pb push_back
#define popb pop_back
#define fi first
#define se second
#define sz size()
// input
template<class T> void IN(T& x) {cin >> x;}
template<class H, class... T> void IN(H& h, T&... t) {IN(h); IN(t...); }
// output
template<class T1, class T2> void OUT(const pair<T1,T2>& x);
template<class T> void OUT(const T& x) {cout << x;}
template<class H, class... T> void OUT(const H& h, const T&... t) {OUT(h); OUT(t...); }
template<class T1, class T2> void OUT(const pair<T1,T2>& x) {OUT(x.fi," ",x.se);}
template<class... T> void OUTL(const T&... t) {OUT(t..., "\n"); }
//===================//
// Added libraries //
//===================//
// mod library
ll MOD=1e9+7;
inline ll mod(ll x_) {
return (x_)%MOD;
}
ll modpow(ll x_, ll N_) {
if(N_ == 0) return 1;
ll a = modpow(x_,N_/2);
a = (a*a)%MOD;
if(N_%2) a = (a*x_)%MOD;
return a;
}
ll inv(ll x_) {
return modpow(x_, MOD-2);
}
class mi {
public:
mi(ll v=0) {value = v;}
mi operator+ (ll rs) {return mod(value+rs);}
mi operator- (ll rs) {return mod(value-rs+MOD);}
mi operator* (ll rs) {return mod(value*rs);}
mi operator/ (ll rs) {return mod(value*inv(rs));}
mi& operator+=(ll rs) {*this = (*this)+rs; return *this;}
mi& operator-=(ll rs) {*this = (*this)-rs; return *this;}
mi& operator*=(ll rs) {*this = (*this)*rs; return *this;}
mi& operator/=(ll rs) {*this = (*this)/rs; return *this;}
operator ll&() {return value;}
ll value;
};
typedef vector<mi> vmi;
//===================//
//end added libraries//
//===================//
void program();
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
program();
}
//===================//
// begin program //
//===================//
const int MX = 5e5;
int n, a[MX];
map<int, int> mp;
set<int> inq;
queue<int> q;
int p[MX], m;
mi dp[MX];
void tryAdd(int x) {
if(inq.count(x)) return;
if(mp[x] >= 2) {
q.push(x);
inq.insert(x);
}
}
void fix(int x) {
int am = mp[x];
int times = am/2;
if(am%2) mp[x] = 1;
else mp.erase(x);
if(x >= 3) {
mp[x-2] += times;
mp[x+1] += times;
tryAdd(x-2);
tryAdd(x+1);
}
if(x == 2) {
mp[1] += times;
mp[3] += times;
tryAdd(1);
tryAdd(3);
}
if(x == 1) {
mp[2] += times;
tryAdd(2);
}
}
void program() {
IN(n);
RE(i,n) IN(a[i]);
RE(i,n) {
mp[a[i]]++;
tryAdd(a[i]);
while(!q.empty()) fix(q.front()), q.pop();
for(auto it=--mp.end(); it!=mp.begin(); it--) {
auto nxt = it;
nxt--;
if(nxt->fi == it->fi-1) {
int nx = it->fi+1;
mp.erase(nxt);
mp.erase(it);
it = mp.insert({nx,1}).fi;
it++;
}
}
p[0] = 0;
int m=1;
for(auto it=mp.begin(); it!=mp.end(); it++)
p[m++] = it->fi;
m--;
dp[0] = 1;
RE1(j,m) {
if(j == 1) dp[j] = (p[j]+1)/2;
else {
int dif = p[j]-p[j-1];
if((dif)%2 == 0)
dp[j] = dp[j-1]*mi((dif)/2) + dp[j-2]*mi((p[j-1]-p[j-2]-1)/2);
else
dp[j] = dp[j-1]*mi((dif+1)/2);
}
}
OUTL((ll)dp[m]);
}
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
3 ms |
4224 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
3 ms |
4224 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
4224 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
3 ms |
4224 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
3 ms |
4224 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
3 ms |
4224 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
