Submission #729965

#	Time	Username	Problem	Language	Result	Execution time	Memory
729965		n0sk1ll	Skyscraper (JOI16_skyscraper)	C++17	20 / 100	715 ms	201740 KiB

skyscraper

#include <bits/stdc++.h>

#define FAST ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);cerr.tie(0)
#define mp make_pair
#define xx first
#define yy second
#define pb push_back
#define pf push_front
#define popb pop_back
#define popf pop_front
#define all(x) x.begin(),x.end()
#define ff(i,a,b) for (int i = a; i < b; i++)
#define fff(i,a,b) for (int i = a; i <= b; i++)
#define bff(i,a,b) for (int i = b-1; i >= a; i--)
#define bfff(i,a,b) for (int i = b; i >= a; i--)

using namespace std;
long double typedef ld;
unsigned int typedef ui;
long long int typedef li;
pair<int,int> typedef pii;
pair<li,li> typedef pli;
pair<ld,ld> typedef pld;
vector<vector<int>> typedef graph;
unsigned long long int typedef ull;
//const int mod = 998244353;
const int mod = 1000000007;







//Note to self: Check for overflow

int a[105];

int dp[16999][16][203];

void solve_megabrute(int n, int L)
{
    sort(a,a+n);
    int ans=0;
    do
    {
        int tmp=0;
        ff(i,1,n) tmp+=abs(a[i]-a[i-1]);
        if (tmp<=L) ans++;
    } while (next_permutation(a,a+n));
    cout<<ans<<"\n";
}

void solve_bitmask(int n, int L)
{
    ff(i,0,n) dp[(1<<i)][i][0]=1;
    ff(mask,0,(1<<n)) ff(lst,0,n) ff(dole,0,n) fff(t,0,L) if (((mask>>lst)&1) && ((mask>>dole)&1) && lst!=dole)
    {
        (dp[mask][lst][t+abs(a[lst]-a[dole])]+=dp[mask^(1<<lst)][dole][t])%=mod;
    }

    int sms=(1<<n)-1;
    int ans=0;
    ff(i,0,n) fff(t,0,L) (ans+=dp[sms][i][t])%=mod;
    
    cout<<ans<<"\n";
}

int main()
{
    FAST;

    int n,L; cin>>n>>L;
    ff(i,0,n) cin>>a[i];
    if (n>14) return cout<<"necu radim",0;

    if (n<=8) solve_megabrute(n,L);
    else solve_bitmask(n,L);
}

//Note to self: Check for overflow

• Subtask 1: 5 / 5
• Subtask 2: 15 / 15
• Subtask 3: 0 / 80