Submission #963261

#	Time	Username	Problem	Language	Result	Execution time	Memory
963261		BhavayGoyal	Skyscraper (JOI16_skyscraper)	C++14	20 / 100	705 ms	106584 KiB

skyscraper

#include <bits/stdc++.h>
using namespace std;

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;

template<class T> using oset = 
            tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

#define ll long long
#define ld long double
#define ar array
#define vi vector<int>
#define vii vector<vector<int>>
#define pii pair<int, int>
#define pb push_back
#define all(x) x.begin(), x.end()
#define f first
#define s second
#define endl "\n"

const int MOD = 1e9+7;
const int inf = 1e9;
const ll linf = 1e18;

const int d4i[4]={-1, 0, 1, 0}, d4j[4]={0, 1, 0, -1};
const int d8i[8]={-1, -1, 0, 1, 1, 1, 0, -1}, d8j[8]={0, 1, 1, 1, 0, -1, -1, -1};

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());


// -------------------------------------------------- Main Code --------------------------------------------------

int n, l;
int arr[16];
vector<vii> dp;

int sol(int mask, int prev, int sum) {
    if (__builtin_popcount(mask) == n) return 1;
    if (dp[mask][prev][sum] != -1) return dp[mask][prev][sum];
    int ans = 0;
    for (int i = 0; i < n; i++) {
        if (mask&(1<<i)) continue;
        int newsum = sum + (prev==n?0:abs(arr[prev]-arr[i]));
        if (newsum <= l) ans = (ans + sol(mask|(1<<i), i, newsum))%MOD;
    }
    return dp[mask][prev][sum] = ans;
}

void sol() {
    cin >> n >> l;
    dp = vector<vii>((1<<n)+1, vii(n+1, vi(l+1, -1)));
    for (int i = 0; i < n; i++) cin >> arr[i];

    cout << sol(0, n, 0) << endl;
}

int main () {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    int t = 1;
    // cin >> t; 
    while (t--) {
        sol();
    }
    return 0;
}

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