Submission #742314

#	Time	Username	Problem	Language	Result	Execution time	Memory
742314		bgnbvnbv	Bitaro’s Party (JOI18_bitaro)	C++14	0 / 100	33 ms	58944 KiB

bitaro

#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=5e5+10;
const ll inf=1e18;
const ll mod=1e9+7;
struct node
{
    ll f,s,val;
    node()
    {
        f=-inf;
        s=-inf;
        val=-inf;
    }
    node operator+(const node&o)
    {
        node ans;
        ans.f=max(f,o.f);
        ans.s=max(s,o.s);
        ans.val=max({-inf,val,o.val,f+o.s});
        return ans;
    }
}st[4*maxN];
ll n;
//ll st[4*maxN];
void update(ll t,ll pos,ll val,ll id=1,ll l=1,ll r=n)
{
    if(pos>r||pos<l) return ;
    if(l==r)
    {
        if(t==1) st[id].f=val;
        else st[id].s=val;
        st[id].val=max(-inf,st[id].f+st[id].s);
        return;
    }
    ll mid=l+r>>1;
    if(pos<=mid) update(t,pos,val,id*2,l,mid);
    else update(t,pos,val,id*2+1,mid+1,r);
    st[id]=st[id*2]+st[id*2+1];
}
node get(ll i,ll j,ll id=1,ll l=1,ll r=n)
{
    if(j<l||r<i) return node();
    if(i<=l&&r<=j) return st[id];
    ll mid=l+r>>1;
    return get(i,j,id*2,l,mid)+get(i,j,id*2+1,mid+1,r);
}
ll q;
ll a[maxN];
vector<pli>adu[maxN];
ll ans[maxN];
void solve()
{
    cin >> n;
    deque<int>dq;
    for(int i=1;i<=n;i++)
    {
        cin >> a[i];
        update(0,i,a[i]);
    }
    cin >> q;
    for(int i=1;i<=q;i++)
    {
        ll l,r;
        cin >> l >> r;
        adu[l].pb({r,i});
    }
    vector<pli>vd;
    for(int i=1;i<=n;i++)
    {
        while(dq.size()>0&&a[i]>=a[dq.back()])
        {
            vd.pb({dq.back(),i});
            dq.pop_back();
        }
        if(dq.size()>0)
        {
            vd.pb({dq.back(),i});
        }
        dq.pb(i);
    }
    sort(vd.begin(),vd.end());
    ll j=(int)vd.size()-1;
    for(int i=n;i>=1;i--)
    {
        while(j>=0&&vd[j].fi>=i)
        {
            update(1,vd[j].se*2-vd[j].fi,a[vd[j].fi]+a[vd[j].se]);
            j--;
        }
        for(auto zz:adu[i])
        {
            ans[zz.se]=get(i,zz.fi).val;
        }
    }
    for(int i=1;i<=q;i++) cout << ans[i]<<'\n';
}
int main()
{
    fastio
    //freopen(TASKNAME".INP","r",stdin);
    //freopen(TASKNAME".OUT","w",stdout);
    solve();
}

Compilation message (stderr)

bitaro.cpp: In function 'void update(ll, ll, ll, ll, ll, ll)':
bitaro.cpp:43:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   43 |     ll mid=l+r>>1;
      |            ~^~
bitaro.cpp: In function 'node get(ll, ll, ll, ll, ll)':
bitaro.cpp:52:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   52 |     ll mid=l+r>>1;
      |            ~^~

• Subtask 1: 0 / 7
• Subtask 2: 0 / 7
• Subtask 3: 0 / 86