Submission #416200

#	Time	Username	Problem	Language	Result	Execution time	Memory
416200		duyanh1704	Global Warming (CEOI18_glo)	C++14	0 / 100	49 ms	6120 KiB

glo

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

const int inf = 2e9 + 29;
int n, x, res;
vector<int> a;

vector<int> LIS(vector<int> a, int k){
    vector<int> f(n + 5, inf); f[0] = -inf;
    vector<int> dp(n, 0);
    f[0] = -inf;
    for (int i = 0; i < n; ++i){
        int k = lower_bound(f.begin(), f.end(), k * a[i]) - f.begin();
        if (i > 0) dp[i] = k;
        else dp[i] = k;
        f[k] = k * a[i];
    }
    return dp;
}

int main(){
    ios::sync_with_stdio(0); cin.tie(0);

    cin >> n >> x;
    for (int i = 1; i <= n; ++i){
        int t; cin >> t;
        a.push_back(t);
    }

    vector<int> f = LIS(a, 1);
    reverse(a.begin(), a.end());
    vector<int> g = LIS(a, -1);
    reverse(g.begin(), g.end());

    for (int i = 0; i < n; ++i)
        res = max(res, f[i] + g[i] - 1);
    cout << res;
}

Compilation message (stderr)

glo.cpp: In function 'std::vector<int> LIS(std::vector<int>, int)':
glo.cpp:13:51: warning: 'k' may be used uninitialized in this function [-Wmaybe-uninitialized]
   13 |         int k = lower_bound(f.begin(), f.end(), k * a[i]) - f.begin();

• Subtask 1: 0 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 13
• Subtask 4: 0 / 10
• Subtask 5: 0 / 20
• Subtask 6: 0 / 17
• Subtask 7: 0 / 25