Submission #235151

#	Time	Username	Problem	Language	Result	Execution time	Memory
235151		kartel	Doktor (COCI17_doktor)	C++14	60 / 100	1096 ms	6136 KiB

doktor

#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
#define in(x) freopen(x, "r", stdin)
#define out(x) freopen(x, "w", stdout)
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC optimize("-O3")
#define F first
#define S second
#define pb push_back
#define N +500500
#define M ll(1e9 + 7)
#define sz(x) (int)x.size()
#define re return
#define oo ll(1e18)
#define el '\n'
#define pii pair <int, int>
using namespace std;
//using namespace __gnu_pbds;
//typedef tree <int, null_type, less_equal <int> , rb_tree_tag, tree_order_statistics_node_update> ordered_set;
typedef long long ll;
typedef long double ld;

int a[N], pr[N], sf[N], i, mid, len, cur, ans, le, ri, n;

int main()
{
    srand(time(0));
    ios_base::sync_with_stdio(0);
    iostream::sync_with_stdio(0);
    ios::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);

//    in("input.txt");
//    out("output.txt");

    cin >> n;
    for (i = 1; i <= n; i++) cin >> a[i];

    for (i = 1; i <= n; i++) pr[i] = pr[i - 1] + (a[i] == i);
    for (i = n; i >= 1; i--) sf[i] = sf[i + 1] + (a[i] == i);

    for (mid = 1; mid <= n; mid++)
    {
        cur = (a[mid] == mid);
        if (ans < cur + pr[mid - 1] + sf[mid + 1])
        {
            ans = cur + pr[mid - 1] + sf[mid + 1];
            le = mid;
            ri = mid;
        }

        for (len = 1; len <= n && mid - len >= 1 && mid + len <= n; len++)
        {
            if (a[mid - len] - mid == len) cur++;
            if (mid - a[mid + len] == len) cur++;
//            cerr << mid - len << " " << mid + len << " " << cur << el;

            if (ans < cur + pr[mid - len - 1] + sf[mid + len + 1])
            {
                ans = cur + pr[mid - len - 1] + sf[mid + len + 1];
                le = mid - len;
                ri = mid + len;
            }
        }
//        cerr << mid << el;
        cur = 0;
        for (len = 1; len <= n && mid - len >= 1 && mid + len - 1 <= n; len++)
        {
            if (a[mid - len] - mid == len - 1) cur++;
            if (mid - a[mid + len - 1] == len) cur++;

            if (ans < cur + pr[mid - len - 1] + sf[mid + len])
            {
                ans = cur + pr[mid - len - 1] + sf[mid + len];
                le = mid - len;
                ri = mid + len - 1;
            }
        }
    }
    cout << a[le] << " " << a[ri];
}

//
//110000
//110000
//001100
//001100
//000011

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10