#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, ps[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];
if (n <= 5000)
{
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;
}
}
}
}
else
{
for (i = 1; i <= n; i++) ps[a[i]] = i;
for (i = n; i >= 1; i--) sf[i] = sf[i + 1] + (a[i] == i);
for (i = 1; i <= n; i++)
{
int l = i, L = l;
int r = ps[i];
int len = r - l + 1;
int kl = sf[r + 1];
for (; l <= r; l++)
if (a[l] == i + len - l + L - 1) kl++;
kl += kol;
if (kl > ans)
{
ans = kl;
le = L;
ri = r;
}
if (a[i] == i) kol++;
}
if (le > ri) swap(le, ri);
}
cout << a[le] << " " << a[ri];
}
//
//110000
//110000
//001100
//001100
//000011
Compilation message
doktor.cpp: In function 'int main()':
doktor.cpp:102:19: error: 'kol' was not declared in this scope
kl += kol;
^~~
doktor.cpp:102:19: note: suggested alternative: 'kl'
kl += kol;
^~~
kl
