Submission #550453

#	Time	Username	Problem	Language	Result	Execution time	Memory
550453		elazarkoren	Boxes with souvenirs (IOI15_boxes)	C++17	100 / 100	757 ms	386648 KiB

boxes

#include <bits/stdc++.h>
#include "boxes.h"
#define x first
#define y second
#define all(v) v.begin(), v.end()
#define chkmin(a, b) a = min(a, b)
#define chkmax(a, b) a = max(a, b)
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int, int> pii;
typedef vector<pii> vii;

const int MAX_N = 1e7 + 5;
const ll infinity = 1e18;

int n, k, l;

ll dpl[MAX_N], dpr[MAX_N];

void CalcL(vi &p) {
    vi d = {0};
    d.reserve(n + 1);
    int ind = 0;
    for (int i = 1; i <= n; i++) {
        while (d[ind] < i - k) ind++;
        dpl[i] = dpl[d[ind]];
        dpl[i] += min<ll>(l, 2 * p[i]);
        while (!d.empty() && dpl[d.back()] > dpl[i]) d.pop_back();
        d.push_back(i);
    }
}

void CalcR(vi &p) {
    vi d = {n + 1};
    d.reserve(n + 1);
    int ind = 0;
    for (int i = n; i >= 0; i--) {
        while (d[ind] > i + k) ind++;
        dpr[i] = dpr[d[ind]];
        dpr[i] += min<ll>(l, 2 * (l - p[i]));
        while (!d.empty() && dpr[d.back()] > dpr[i]) d.pop_back();
        d.push_back(i);
    }
}

long long delivery(int N, int K, int L, int P[]) {
    n = N, k = K, l = L;
    vi p(n + 1);
    ll ans = infinity;
    for (int i = 1; i <= n; i++) p[i] = P[i - 1];
    CalcL(p), CalcR(p);
    for (int ind = 1; ind <= n + 1; ind++) {
        chkmin(ans, dpl[ind - 1] + dpr[ind]);
    }
    return ans;
}
//3 2 8
//1 2 5

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