Submission #1103961

#	Time	Username	Problem	Language	Result	Execution time	Memory
1103961		vjudge1	Global Warming (CEOI18_glo)	C++17	100 / 100	44 ms	4340 KiB

glo

#include <bits/stdc++.h>
using namespace std;
const int N = 2e5 + 1;
const int INF = 2e9;
int arr[N] , ans;
int l[N] , r[N];
vector<int> dp;
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL); cout.tie(NULL);
    int n,x; cin >> n >> x;
    for (int i=1;i<=n;i++) cin >> arr[i];
    for (int i=1;i<=n;i++) {
        int idx = lower_bound(dp.begin(), dp.end(), arr[i]) - dp.begin();
        l[i] = idx + 1;
        if (idx==dp.size()) dp.push_back(arr[i]);
        dp[idx] = arr[i];
    }
    dp.clear();
    for(int i=n;i>=1;i--) {
        int idx = lower_bound(dp.begin(), dp.end(), -arr[i] + x) - dp.begin();
        r[i] = idx + 1;
        idx = lower_bound(dp.begin(), dp.end(), -arr[i]) - dp.begin();
        if (idx==dp.size()) dp.push_back(-arr[i]);
        dp[idx] = -arr[i];
    }
    int ans = 0;
    for (int i=1;i<=n;i++) ans = max(ans, l[i] + r[i] - 1);
    cout << ans;
    return 0;
}

Compilation message (stderr)

glo.cpp: In function 'int main()':
glo.cpp:16:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |         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