This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
//    freopen("warming.in", "r", stdin);
//    freopen("warming.out", "w", stdout);
    int n;
    cin >> n;
    int h[n];
    pair<int, int> sh2[n];
    for(int i = 0; i < n; i++) {
        cin >> h[i];
        sh2[i].first = h[i];
        sh2[i].second = i;
    }
    sort(sh2, sh2+n);
    int mx_islands = 0;
    int islands = 0;
    for(int i = 0; i < n; i++) {
        if(max(0, h[i])>0 && (i==0 || max(0, h[i-1])==0)) islands++;
    }
    mx_islands = max(mx_islands, islands);
    for(int i = 0; i < n; i++) {
        if(sh2[i].first==sh2[i-1].first && abs(sh2[i].second-sh2[i-1].second)<=1) continue;
        int s = sh2[i].second;
        int e = sh2[i].second;
        while(e+1<n && h[e] == h[e+1]) e++;
        if(s==0 && e == n-1) {
            islands = 0;
        } else if(s==0 && h[e+1]<h[s]) {
            islands--;
        } else if(e==n-1 && h[s-1]<h[e]) {
            islands--;
        } else {
            if(h[s-1]>h[s] && h[e+1]>h[e]) {
                islands++;
                mx_islands = max(mx_islands, islands);
            } else if(h[s-1]<h[s] && h[e+1]<h[e]) {
                islands--;
            }
        }
    }
    cout << mx_islands << endl;
    return 0;
}
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