Submission #990133

#	Time	Username	Problem	Language	Result	Execution time	Memory
990133		crafticat	Boxes with souvenirs (IOI15_boxes)	C++17	20 / 100	2 ms	444 KiB

boxes

#include <bits/stdc++.h>

using namespace std;
using ll = long long;

long long delivery(int N, int K, int L, int p[]) {
    vector<int> prefix(N), suffix(N);
    for (int i = 0; i < N; ++i) {
        prefix[i] = p[i] + min(p[i],L - p[i]);
        suffix[N - i - 1] = L - p[i] + min(p[i], L - p[i]);
    }

    ll best = 1e18;
    for (int i = 0; i <= N; ++i) {
        //Till I is left
        ll ans = 0;
        ll t = i - 1;
        ll j = -1;
        while (j < t) {
            ll jump = t - j;
            if (jump > K) jump = K;
            if (jump == 0) break;
            j += jump;
            ans += prefix[j];
        }
        j = -1;
        t = N - i - 1;
        while (j < t) {
            ll jump = t - j;
            if (jump > K) jump = K;
            if (jump == 0) break;
            j += jump;
            ans += suffix[j];
        }
        best = min(best, ans);
    }
    return best;
}
#if DEBUG
static char _buffer[1024];
static int _currentChar = 0;
static int _charsNumber = 0;
static FILE *_inputFile, *_outputFile;

static inline int _read() {
    if (_charsNumber < 0) {
        exit(1);
    }
    if (!_charsNumber || _currentChar == _charsNumber) {
        _charsNumber = (int)fread(_buffer, sizeof(_buffer[0]), sizeof(_buffer), _inputFile);
        _currentChar = 0;
    }
    if (_charsNumber <= 0) {
        return -1;
    }
    return _buffer[_currentChar++];
}

static inline int _readInt() {
    int c, x, s;
    c = _read();
    while (c <= 32) c = _read();
    x = 0;
    s = 1;
    if (c == '-') {
        s = -1;
        c = _read();
    }
    while (c > 32) {
        x *= 10;
        x += c - '0';
        c = _read();
    }
    if (s < 0) x = -x;
    return x;
}

int main() {
    int N, K, L, i; cin >> N >> K >> L;

    int *p = (int*)malloc(sizeof(int) * (unsigned int)N);

    for (i = 0; i < N; i++) {
        cin >> p[i];
    }

    cout << delivery(N, K, L, p);
    return 0;
}
#endif

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 0 / 15
• Subtask 4: 0 / 15
• Subtask 5: 0 / 20
• Subtask 6: 0 / 30