Submission #1103052

#	Time	Username	Problem	Language	Result	Execution time	Memory
1103052		kingdragon	Global Warming (CEOI18_glo)	C++14	100 / 100	266 ms	19648 KiB

glo

#include <bits/stdc++.h>
#define F first
#define S second
#define pb push_back
#define ll long long
#define ii pair<int,int>
#define iii pair<int,pair<int,int>>
#define iil pair<ll,ll>
#define iiil pair<ll,pair<ll,ll>>
#define oo 1e18
#define check(n) (prime[n>>6]&(1<<((n&63)>>1)))
#define set(n) prime[n>>6]|=(1<<((n&63)>>1))
using namespace std;
const int N=2e5+5;
const ll Mod=1e9+7;
const ll MOD=13141702292180207;
const int dx[]={-1,0,0,1};
const int dy[]={0,-1,1,0};
 
 
int n, a[N], st[4*N], d[N], cnt[N];
int t[N], s[N], x;
set<int> m;
vector<int> b;
void up(int id,int l,int r, int u,int val)
{
    if (u>r || l>u || l>r) return;
    if (l==r)
    {
        st[id]=max(st[id],val);
        return;
    }
    int mid=(l+r)/2;
    up(id*2,l,mid,u,val);
    up(id*2+1,mid+1,r,u,val);
    st[id]=max(st[id*2],st[id*2+1]);
}
 
int get(int id,int l,int r,int u,int v)
{
    if (l>r || u>v || l>v || u>r) return 0;
    if (u<=l && r<=v) return st[id];
    int mid=(l+r)/2;
    return max(get(id*2,l,mid,u,v), get(id*2+1,mid+1,r,u,v));
}
void slove()
{
    cin >> n >> x; 
    m.insert(-500);
    for (int i=1;i<=n;i++)
    {
        cin >> a[i];
        d[i]=2e9+5;
        m.insert(a[i]);
    }
    for (int i: m) b.pb(i); 
    m.clear();
    for (int i=1;i<=n;i++)
    {
        int vt=lower_bound(d+1,d+1+n,a[i])-d;
        d[vt]=a[i];
        t[i]=vt;
        // t[i]: độ dài dãy con tăng dài nhất từ 1->i
    }
    for (int i=1;i<=n;i++) d[i]=2e9+5;
    for (int i=n;i>=1;i--)
    {
        int vt=lower_bound(d+1,d+1+n,-a[i])-d;
        d[vt]=-a[i];
        s[i]=vt;
        // s[i]  độ dài dãy con tăng dài nhất từ i->n
    }
    b.pb(2e9+5);
    int ans=0;
    // giả sử từ 1->i trừ đi x đơn vị = từ i+1 -> n tăng lên x đơn vị

    for (int i=1;i<n;i++)
    {
        int vt=lower_bound(b.begin(),b.end(),a[i])-b.begin();
        up(1,1,n,vt,t[i]);
        vt=lower_bound(b.begin(),b.end(),a[i+1]+x)-b.begin();
        vt--;
        ans=max(ans,s[i+1]+get(1,1,n,1,vt));
    }
    cout << ans;
 
}
int main()
{
    // freopen("test.inp","r",stdin);
    // freopen("test.out","w",stdout);
    ios_base::sync_with_stdio(0);
    cout.tie(0); cin.tie(0);
    int T=1;
    //cin >> T;
    while(T--) slove();
}

• 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