Submission #1007109

#	Time	Username	Problem	Language	Result	Execution time	Memory
1007109		The_Samurai	Boxes with souvenirs (IOI15_boxes)	C++17	100 / 100	588 ms	293968 KiB

boxes

#include "boxes.h"
#include "bits/stdc++.h"
using namespace std;
using ll = long long;

ll delivery(int n, int k, int L, int p[]) {
    auto dist = [&](int i, int j) -> int {
        return min(abs(i - j), L - abs(i - j));  
    };
    sort(p, p + n);
    vector<ll> pref(n), suff(n + 1);
    for (int i = 0; i < n; i++) {
        pref[i] = p[i] + dist(0, p[i]);
        if (i >= k) pref[i] += pref[i - k];
        // for (int j = i; j < min(n, i + k); j++) {
        //     pref[j] = i > 0 ? pref[i - 1] : 0;
        //     pref[j] += p[j] + dist(0, p[j]);
        // }
    }
    for (int i = n - 1; i >= 0; i--) {
        suff[i] = (L - p[i]) + dist(0, p[i]);
        if (i + k < n) suff[i] += suff[i + k];
        // for (int j = i; j >= max(0, i - k + 1); j--) {
        //     suff[j] = suff[i + 1];
        //     suff[j] += (L - p[j]) + dist(0, p[j]);
        // }
    }
    ll ans = min(pref[n - 1], suff[0]);
    for (int i = 1; i < n; i++) {
        ans = min(ans, pref[i - 1] + suff[i]);
    }
    return ans;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 15 / 15
• Subtask 4: 15 / 15
• Subtask 5: 20 / 20
• Subtask 6: 30 / 30