Submission #548813

#	Time	Username	Problem	Language	Result	Execution time	Memory
548813		AKiko	Safety (NOI18_safety)	C++14	29 / 100	2065 ms	3224 KiB

safety

#include <bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define ss second
#define ff first
#define pb push_back
#define pii pair<int, int>
#define INF INT_MAX
using namespace std;
void debug_out() { cerr << endl; }
template<typename Head, typename... Tail> void debug_out(Head H, Tail... T) { cerr << ' ' << H; debug_out(T...); }
#ifdef AKIKO_DEBUG
#define debug(...) cerr << "\033[1;31m(" << #__VA_ARGS__ << "):\033[0m", debug_out(__VA_ARGS__)
#else
#define debug(...)
#endif

#define FAST ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);

const ll MOD = 1e9 + 7;
const int N = 5e3 + 1;
int n, h;
vector<ll> a;



void go () {
    sort(a.begin(), a.end());
    vector<ll> pres(n);
    for(int i = 0; i < n; i++) {
        if(i == 0) {
            pres[i] = a[i];
        } else {
            pres[i] = a[i] + pres[i - 1];
        }
    }
    ll ans = INT64_MAX;
    for(ll i = 0; i < n; i++) {
        ll x = a[i];
        ll temp = (x * i) - (i > 0 ? pres[i - 1] : 0);
        ll sum = pres[n - 1] - (i > 0 ? pres[i - 1] : 0);
        temp += sum - (n - i) * x;
        ans = min(ans, temp);
    }
    cout << ans << "\n";
}

int main() {
    cin >> n >> h;
    a.resize(n);
    h = min (h, N);
    for(int i = 0; i < n; i++) {
        cin >> a[i];
    }

    if(h == 0) {
        go();
        return 0;
    }
    vector<int> prev(N), cur(N);
    for(int i = 0; i < N; i++) {
        prev[i] = abs(a[0] - i);
    }
    
    for(int i = 1; i < n; i++) {
        set<pii> s;
        for(int j = 0; j <= h; j++) {
            s.insert({prev[j], j});
        }
        for(int j = 0; j < N; j++) {
            cur[j] = (*s.begin()).ff + abs(a[i] - j);
            if(j >= h)
                s.erase({prev[j - h], j - h});
            if(j + h + 1 < N) 
                s.insert({prev[j + h + 1], j + h + 1});
        }
        prev = cur;
    }

    int ans = INF;
    for(int i = 0; i < N; i++) {
        ans = min(ans, cur[i]);
    }
    cout << ans << "\n";



    return 0;
}

/* stuff you should look for
    * int overflow, array bounds
    * special cases (n=1?)
    * do smth instead of nothing and stay organized
    * WRITE STUFF DOWN
    * DON'T GET STUCK ON ONE APPROACH
*/

• Subtask 1: 3 / 3
• Subtask 2: 4 / 4
• Subtask 3: 0 / 9
• Subtask 4: 5 / 5
• Subtask 5: 6 / 6
• Subtask 6: 11 / 11
• Subtask 7: 0 / 11
• Subtask 8: 0 / 22
• Subtask 9: 0 / 29