Submission #720473

#	Time	Username	Problem	Language	Result	Execution time	Memory
720473		fdnfksd	Global Warming (CEOI18_glo)	C++14	100 / 100	554 ms	14936 KiB

glo

#include<bits/stdc++.h>
#define TASKNAME "codeforce"
#define pb push_back
#define pli pair<int,int>
#define fi first
#define se second
#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL);
using namespace std;
using ll=long long;
const ll maxN=2e5+10;
const ll inf=0;
const ll mod=1e9+7;
ll n,a[maxN];
ll st[4*maxN];
void build()
{
    fill(st,st+4*maxN,-inf);
}
void update(ll pos,ll val,ll id=1,ll l=1,ll r=n)
{
    if(l==r)
    {
        st[id]=max(st[id],val);
        return;
    }
    ll mid=l+r>>1;
    if(pos<=mid) update(pos,val,id*2,l,mid);
    else update(pos,val,id*2+1,mid+1,r);
    st[id]=max(st[id*2],st[id*2+1]);
}
ll get(ll i,ll j,ll id=1,ll l=1,ll r=n)
{
    if(j<l||r<i) return -inf;
    if(i<=l&&r<=j) return st[id];
    ll mid=l+r>>1;
    return max(get(i,j,id*2,l,mid),get(i,j,id*2+1,mid+1,r));
}
ll x,dp1[maxN],dp2[maxN];
vector<ll>vec;
void solve()
{
    cin >> n >> x;
    vec.pb(-1);
    for(int i=1;i<=n;i++) cin >>a[i],vec.pb(a[i]);
    sort(vec.begin(),vec.end());
    for(int i=1;i<=n;i++)
    {
        ll p=lower_bound(vec.begin(),vec.end(),a[i])-vec.begin()-1;
        dp1[i]=max(1ll,get(1,p)+1);
        p++;
        update(p,dp1[i]);
    }
    build();
    for(int i=n;i>=1;i--)
    {
        ll p=upper_bound(vec.begin(),vec.end(),a[i])-vec.begin();
        dp2[i]=max(1ll,get(p,n)+1);
        p--;
        update(p,dp2[i]);
    }
    build();
    ll ans=dp1[n];
    for(int i=1;i<=n;i++)
    {
        ll p=lower_bound(vec.begin(),vec.end(),a[i]+x)-vec.begin()-1;
        ans=max(ans,dp2[i]+get(1,p));
        p=lower_bound(vec.begin(),vec.end(),a[i])-vec.begin();
        update(p,dp1[i]);
    }
    build();
    for(int i=n;i>=1;i--)
    {
        ll p=upper_bound(vec.begin(),vec.end(),a[i]-x)-vec.begin();
        ans=max(ans,dp1[i]+get(p,n));
        p=lower_bound(vec.begin(),vec.end(),a[i])-vec.begin();
        update(p,dp2[i]);
    }
    cout << ans;
}
int main()
{
    fastio
    //freopen(TASKNAME".INP","r",stdin);
    //freopen(TASKNAME".OUT","w",stdout);
    solve();
}

Compilation message (stderr)

glo.cpp: In function 'void update(ll, ll, ll, ll, ll)':
glo.cpp:26:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   26 |     ll mid=l+r>>1;
      |            ~^~
glo.cpp: In function 'll get(ll, ll, ll, ll, ll)':
glo.cpp:35:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   35 |     ll 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