Submission #246259

#	Time	Username	Problem	Language	Result	Execution time	Memory
246259		SamAnd	Safety (NOI18_safety)	C++17	24 / 100	2086 ms	65676 KiB

safety

#include <bits/stdc++.h>
using namespace std;
#define m_p make_pair
#define all(x) (x).begin(),(x).end()
#define sz(x) ((int)(x).size())
#define fi first
#define se second
typedef long long ll;
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
mt19937 rnf(2106);
const int N = 5003, m = 5000, INF = 1000000009;

int n, h;
int a[N];

int dp[N][N];

int t[N * 4];

void bil(int tl, int tr, int a[], int pos)
{
    if (tl == tr)
    {
        t[pos] = a[tl];
        return;
    }
    int m = (tl + tr) / 2;
    bil(tl, m, a, pos * 2);
    bil(m + 1, tr, a, pos * 2 + 1);
    t[pos] = min(t[pos * 2], t[pos * 2 + 1]);
}

int qry(int tl, int tr, int l, int r, int pos)
{
    if (l > r)
        return INF;
    if (tl == l && tr == r)
        return t[pos];
    int m = (tl + tr) / 2;
    return min(qry(tl, m, l, min(m, r), pos * 2),
               qry(m + 1, tr, max(m + 1, l), r, pos * 2 + 1));
}

void solv()
{
    scanf("%d%d", &n, &h);
    for (int i = 1; i <= n; ++i)
        scanf("%d", &a[i]);
    for (int j = 0; j <= m; ++j)
    {
        dp[1][j] = abs(a[1] - j);
    }
    for (int i = 2; i <= n; ++i)
    {
        bil(0, m, dp[i - 1], 1);
        for (int j = 0; j <= m; ++j)
        {
            dp[i][j] = abs(a[i] - j) + qry(0, m, max(0, j - h), min(m, j + h), 1);
        }
    }
    int ans = INF;
    for (int j = 0; j <= m; ++j)
        ans = min(ans, dp[n][j]);
    printf("%d\n", ans);
}

int main()
{
    #ifdef SOMETHING
    freopen("input.txt", "r", stdin);
    //freopen("output.txt", "w", stdout);
    #endif // SOMETHING
    //ios_base::sync_with_stdio(false), cin.tie(0);
    solv();
    return 0;
}

//while ((double)clock() / CLOCKS_PER_SEC <= 0.9){}

Compilation message (stderr)

safety.cpp: In function 'void solv()':
safety.cpp:46:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d", &n, &h);
     ~~~~~^~~~~~~~~~~~~~~~
safety.cpp:48:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &a[i]);
         ~~~~~^~~~~~~~~~~~~

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