Submission #1028021

#	Time	Username	Problem	Language	Result	Execution time	Memory
1028021		rsinventor	Global Warming (NOI13_gw)	C++17	0 / 40	5 ms	912 KiB

gw

#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];
    vector<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.begin(), sh2.end());

    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;
}

Compilation message (stderr)

gw.cpp: In function 'int main()':
gw.cpp:9:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    9 |     freopen("warming.in", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
gw.cpp:10:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   10 |     freopen("warming.out", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 6
• Subtask 2: 0 / 6
• Subtask 3: 0 / 7
• Subtask 4: 0 / 10
• Subtask 5: 0 / 11