Submission #525471

#	Time	Username	Problem	Language	Result	Execution time	Memory
525471		ammar2000	Global Warming (CEOI18_glo)	C++17	100 / 100	54 ms	8544 KiB

glo

#include<bits/stdc++.h>
#define ll long long
#define pb push_back
#define F first
#define S second
#define coy cout<<"YES\n"
#define con cout<<"NO\n"
#define co1 cout<<"-1\n"
#define sc(x) scanf("%lld",&x)
#define all(x) x.begin(),x.end()
#define fast ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
using namespace std;
const int SI=3e5+7;
ll INF=8e18+7;
int dx[] = {1 , -1 , 0 , 0};
int dy[] = {0 , 0 , 1 , -1};
int MOD=1e9+7;
ll n,x,a[SI],pr[SI];
int main()
{
   fast
   cin>>n>>x;
   for (int i=0;i<n;i++)
     cin>>a[i];
   vector <ll> dp(n,INF);
   for (int i=0;i<n;i++)
   {
       ll j=lower_bound(dp.begin(),dp.end(),a[i])-dp.begin();
       dp[j]=a[i];
       pr[i]=j+1;
   }
   ll ans=0;
   vector <ll> dp2(n,INF);
   for (int i=n-1;i>=0;i--)
   {
       ll j=lower_bound(dp2.begin(),dp2.end(),-a[i]+x)-dp2.begin();
       ans=max(ans,pr[i]+j);
       j=lower_bound(dp2.begin(),dp2.end(),-a[i])-dp2.begin();
       dp2[j]=-a[i];
   }
   cout <<ans<<"\n";
   // use scanf not cin
   return 0;
}

• 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