Submission #973310

#	Time	Username	Problem	Language	Result	Execution time	Memory
973310		njoop	Global Warming (CEOI18_glo)	C++17	100 / 100	49 ms	4316 KiB

glo

#include <bits/stdc++.h>

using namespace std;

int n, x, idx, arr[200010], pre[200010], ans;
vector<int> dp;

int main() {
    cin.tie(0)->sync_with_stdio(0);
    cin >> n >> x;
    for(int i=1; i<=n; i++) {
        cin >> arr[i];
        idx = lower_bound(dp.begin(), dp.end(), arr[i]) - dp.begin();
        if(idx == dp.size()) dp.push_back(arr[i]);
        else dp[idx] = arr[i];
        pre[i] = idx+1;
        ans = max(ans, pre[i]);
    }
    dp.clear();
    for(int i=n; i>0; i--) {
        idx = lower_bound(dp.begin(), dp.end(), -arr[i]+x) - dp.begin();
        ans = max(ans, pre[i] + idx);
        idx = lower_bound(dp.begin(), dp.end(), -arr[i]) - dp.begin();
        if(idx == dp.size()) dp.push_back(-arr[i]);
        else dp[idx] = -arr[i];
    }
    cout << ans;
    return 0;
}

Compilation message (stderr)

glo.cpp: In function 'int main()':
glo.cpp:14:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |         if(idx == dp.size()) dp.push_back(arr[i]);
      |            ~~~~^~~~~~~~~~~~
glo.cpp:24:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |         if(idx == dp.size()) dp.push_back(-arr[i]);
      |            ~~~~^~~~~~~~~~~~

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