Submission #1108391

#	Time	Username	Problem	Language	Result	Execution time	Memory
1108391		koukirocks	Global Warming (CEOI18_glo)	C++17	100 / 100	41 ms	5072 KiB

glo

#include <bits/stdc++.h>
#define speed ios_base::sync_with_stdio(0); cin.tie(0)
#define all(x) (x).begin(),(x).end()
#define F first
#define S second
//#pragma GCC optimize("O3,unroll-loops")
//#pragma GCC target("avx,avx2")
//#pragma GCC target("popcnt")
 
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef double db;
typedef long double ldb;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
 
const ll MAX=2e5+10,P=1e9+7;
const ll INF=0x3f3f3f3f,oo=0x3f3f3f3f3f3f3f3f;
const ldb eps=1e-6;
const ldb PI=acos(-1.0);
const int dir[4][2]={{0,1},{0,-1},{1,0},{-1,0}};
template<typename T>
using vvector = vector<vector<T>>;

int main() {
    speed;
    int n,x;
    cin>>n>>x;
    vector<int> a(n+1);
    vector<int> dp(n+1);
    for (int i=1;i<=n;i++) {
        cin>>a[i];
    }
    vector<int> curr;
    for (int i=1;i<=n;i++) {
        if (curr.empty() or curr.back()<a[i]) {
            curr.push_back(a[i]);
            dp[i]=curr.size();
        } else {
            auto it = lower_bound(all(curr),a[i]);
            *it = a[i];
            dp[i]=it-curr.begin()+1;
        }
        // cout<<dp[i]<<" ";
    }
    // cout<<"dp\n";
    curr.clear();
    vector<int> dp2(n+1);
    for (int i=n;i>=1;i--) {
        if (curr.empty() or curr.back()>a[i]-x) dp2[i]=curr.size()+1;
        else {
            int l=0,r=curr.size()-1;    
            while (l<r) {
                int mid=l+r>>1;
                if (curr[mid]<=a[i]-x) r=mid;
                else l=mid+1;
            }
            dp2[i]=l+1;
        }
        if (curr.empty() or curr.back()>a[i]) curr.push_back(a[i]);
        else {
            int l=0,r=curr.size()-1;    
            while (l<r) {
                int mid=l+r>>1;
                if (curr[mid]<=a[i]) r=mid;
                else l=mid+1;
            }
            curr[l]=a[i];
        }
        // cout<<dp2[i]<<" ";
    }
    // cout<<"dp2\n";
    int ans=0;
    for (int i=1;i<=n;i++) {
        // cout<<dp[i]<<" "<<dp2[i]<<" dp dp2\n";
        ans=max(ans,dp[i]+dp2[i]-1);
    }
    cout<<ans<<"\n";
    return 0;
}

/*
10 10
2 34 545 56 3 3 65 2 7 6
*/

Compilation message (stderr)

glo.cpp: In function 'int main()':
glo.cpp:55:26: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   55 |                 int mid=l+r>>1;
      |                         ~^~
glo.cpp:65:26: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   65 |                 int mid=l+r>>1;
      |                         ~^~

• 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