Submission #92663

#	Time	Username	Problem	Language	Result	Execution time	Memory
92663		toloraia	Money (IZhO17_money)	C++14	0 / 100	5 ms	4344 KiB

money

#include <bits/stdc++.h>
using namespace std;

const int MAXN = 1e6;

int n;
int a[MAXN + 5];
int b[MAXN + 5];
int A[MAXN + 5][25], B[MAXN + 5][25];
int le[MAXN + 5];
int dp[MAXN + 5];

int datvla (int l, int r){
    if (l > r)
        return n + 1;
    int x = 0, y = 1;
    while (y * 2 < r - l + 1){
        x++;
        y *= 2;
    }
    return min (A[l][x], B[r][x]);
}

int main()
{
    cin>>n;
    for (int i = 1; i <= n; i++)
        cin>>a[i];
    for (int i = 1; i <= MAXN; i++)
        b[i] = n + 1;
    for (int i = n; i >= 1; i--)
        b[a[i]] = i;
    for (int i = 1; i <= n; i++){
        A[i][0] = b[i];
        B[i][0] = b[i];
    }
    for (int i = 1; i < 20; i++)
        for (int j = 1; j <= n; j++){
            A[j][i] = A[j][i - 1];
            if (j + (1<<(i - 1)) <= n)
                A[j][i] = min (A[j][i], A[j + (1<<(i - 1))][i - 1]);
            B[j][i] = B[j][i - 1];
            if (j - (1<<(i - 1)) >= 1)
                B[j][i] = min (B[j][i], B[j - (1<<(i - 1))][i - 1]);
        }
    le[1] = 1;
    for (int i = 2; i <= n; i++){
        le[i] = i;
        if (a[i] >= a[i - 1])
            le[i] = le[i - 1];
    }
    dp[1] = 1;
    for (int i = 2; i <= n; i++){
        int I = i;
        for (int j = 19; j >= 0; j--){
            if (I - (1<<j) < le[i])
                continue;
            if (datvla (a[I - (1<<j)], a[i]) >= I - (1<<j))
                I -= (1<<j);
        }
        dp[i] = dp[I - 1] + 1;
    }
    cout<<dp[n]<<endl;
    return 0;
}

• Subtask 1: 0 / 9
• Subtask 2: 0 / 16
• Subtask 3: 0 / 20
• Subtask 4: 0 / 55