Submission #852736

#	Time	Username	Problem	Language	Result	Execution time	Memory
852736		sleepntsheep	Secret (JOI14_secret)	C++17	0 / 100	20089 ms	4636 KiB

secret

#include <vector>
#include "secret.h"
#include <assert.h>
#define N 1050

int n, *a;
std::vector<int> pre[N<<1], suf[N<<1];

void build(int v, int l, int r)
{
    if (l == r)
    {
        pre[v] = suf[v] = {a[l]};
        return;
    }
    int m=(l+r)/2, vl=v+1, vr=v+(m-l+1)*2;
    suf[v].resize(m-l+1);
    suf[v][m-l] = a[m];
    for (int i = m-l-1, j = m - 1; j >= l; --j, --i)
        suf[v][i] = Secret(a[j], suf[v][i+1]);
    pre[v].resize(r-m);
    pre[v][0] = a[m+1];
    for (int i = 1; i < r-m; ++i)
        pre[v][i] = Secret(pre[v][i-1], a[m+1+i]);
    build(vl, l, m);
    build(vr, m+1, r);
}

int qry(int v, int l, int r, int x, int y)
{
    int m = (l+r)/2, vl=v+1, vr=v+(m-l+1)*2;

    if (l <= x && y <= m) return qry(vl, l, m, x, y);
    if (m + 1 <= x && y <= r) return qry(vr, m+1, r, x, y);

    int al = suf[v][suf[v].size()-1-(m-x)], ar = pre[v][y-m-1];
    return Secret(al, ar);
}

void Init(int n_, int *a_)
{
    n = n_, a = a_;
    build(0, 0, n-1);
}

int Query(int l, int r)
{
    return qry(0, 0, n-1, l, r);
}

• Subtask 1: 0 / 100