Submission #559496

#	Time	Username	Problem	Language	Result	Execution time	Memory
559496		zaneyu	Global Warming (CEOI18_glo)	C++14	100 / 100	66 ms	5380 KiB

glo

/*input
8 10
7 3 5 12 2 7 3 4
*/
#include<bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
typedef tree<long long,null_type,less_equal<long long>,rb_tree_tag,tree_order_statistics_node_update> indexed_set;
#pragma GCC optimize("Ofast")
//#pragma GCC target("avx2")
//order_of_key #of elements less than x
// find_by_order kth element
using ll=long long;
using ld=long double;
using pii=pair<ll,ll>;
#define f first
#define s second
#define pb push_back
#define REP(i,n) for(int i=0;i<n;i++)
#define REP1(i,n) for(ll i=1;i<=n;i++)
#define FILL(n,x) memset(n,x,sizeof(n))
#define ALL(_a) _a.begin(),_a.end()
#define sz(x) (int)x.size()
#define SORT_UNIQUE(c) (sort(c.begin(),c.end()),c.resize(distance(c.begin(),unique(c.begin(),c.end()))))
const ll maxn=2e5+5;
const ll maxlg=__lg(maxn)+2;
const ll INF64=4e18;
const int INF=0x3f3f3f3f;
const ll MOD=1e9+7;
const ld PI=acos(-1);
const ld eps=1e-9;
#define lowb(x) x&(-x)
#define MNTO(x,y) x=min(x,(__typeof__(x))y)
#define MXTO(x,y) x=max(x,(__typeof__(x))y)
template<typename T1,typename T2>
ostream& operator<<(ostream& out,pair<T1,T2> P){
    out<<P.f+1<<' '<<P.s+1;
    return out;
}
template<typename T>
ostream& operator<<(ostream& out,vector<T> V){
    REP(i,sz(V)) out<<V[i]<<((i!=sz(V)-1)?"\n":"");
    return out;
}
ll mult(ll a,ll b){
    return a*b%MOD;
}
ll mult(ll a,ll b,ll mod){
    ll res=0;
    while(b){
        if(b&1) res=(res+a)%mod;
        a=(a+a)%mod;
        b>>=1;
    }
    return res;
}
ll mypow(ll a,ll b,ll mod){
    if(b<=0) return 1;
    a%=mod;
    ll res=1LL;
    while(b){
        if(b&1) res=(res*a)%mod;
        a=(a*a)%mod;
        b>>=1;
    }
    return res;
}

ll mypow(ll a,ll b){
    a%=MOD;
    if(a==0) return 0;
    if(b<=0) return 1;
    ll res=1LL;
    while(b){
        if(b&1) res=(res*a)%MOD;
        a=(a*a)%MOD;
        b>>=1;
    }
    return res;
}
int arr[maxn];
int dp[maxn];
int main(){
    ios::sync_with_stdio(false),cin.tie(0);
    int n,x;
    cin>>n>>x;
    REP(i,n) cin>>arr[i];
    vector<int> v(n,INF);
    REP(i,n){
        int p=lower_bound(ALL(v),arr[i])-v.begin();
        v[p]=arr[i];
        dp[i]=p+1;
    }
    v=vector<int>(n,INF);
    int ans=0;
    for(int i=n-1;i>=0;i--){
        int len=lower_bound(ALL(v),x-arr[i])-v.begin();
        MXTO(ans,dp[i]+len);
        v[lower_bound(ALL(v),-arr[i])-v.begin()]=-arr[i];
    }
    cout<<ans;
}

• 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