Submission #1092721

#	Time	Username	Problem	Language	Result	Execution time	Memory
1092721		De3b0o	Arboras (RMI20_arboras)	C++17	0 / 100	43 ms	40276 KiB

arboras

#include<bits/stdc++.h>
#include<random>
#define ll long long
#define F first
#define S second
#define in insert
#define pb push_back
#define ppb pop_back()
#define d3 ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define cans cout << ans << "\n";
#define yes cout << "Yes" << "\n";
#define no cout << "No" << "\n";
#define pll pair<ll,ll>
#define lin cout << "\n";
#define sqr 340
#define mid ((l+r)/2)
#define lc (2*x)
#define rc (2*x+1)

using namespace std;

const ll N = 100009;
const ll m = 1e9+7;

ll n , q , ans;
ll p[N] , d[N];
ll path[N];
ll dp[N];
vector<ll> adj[N];
multiset<ll> v[N];

void dfs(ll x)
{
    path[x]=0;
    for(auto it : adj[x])
    {
        dfs(it);
        v[x].in(path[it]+d[it]);
    }
    if(v[x].size()==0)
        dp[x]=0;
    else if(v[x].size()==1)
        dp[x]=*(--v[x].end());
    else
    {
        auto it = (--v[x].end());
        dp[x]=*it;
        it--;
        dp[x]+=*it;
    }
    dp[x]%=m;
    ans+=dp[x];
    ans%=m;
    if(v[x].size())
        path[x]=*(--v[x].end());
}

int main()
{
    d3
    cin >> n;
    p[0]=-1;
    for(int i = 1 ; n>i ; i++)
    {
        cin >> p[i];
        adj[p[i]].pb(i);
    }
    d[0]=0;
    for(int i = 1 ; n>i ; i++)
        cin >> d[i];
    dfs(0);
    cans
    cin >> q;
    while(q--)
    {
        ll val , ad;
        cin >> val >> ad;
        ll pr = val;
        ll sum = path[val];
        d[val]+=ad;
        if(path[p[pr]]==path[pr]+d[pr]-ad)
        {
            while(p[pr]!=-1)
            {
                ll np = p[pr];
                ans-=dp[np];
                ans%=m;
                ans+=m;
                ans%=m;
                sum+=d[pr];
                auto it = v[np].find(sum-ad);
                v[np].erase(it);
                v[np].in(sum);
                if(v[np].size()==0)
                    dp[np]=0;
                else if(v[np].size()==1)
                    dp[np]=*(--v[np].end());
                else
                {
                    auto itt = (--v[np].end());
                    dp[np]=*itt;
                    itt--;
                    dp[np]+=*itt;
                }
                dp[np]%=m;
                ans+=dp[np];
                ans%=m;
                if(v[np].size())
                    path[np]=*(--v[np].end());
                pr=np;
            }
        }
        else
        {
            ll np = p[pr];
            ans-=dp[np];
            ans%=m;
            ans+=m;
            ans%=m;
            auto it = v[np].find(path[pr]+d[pr]-ad);
            v[np].erase(it);
            v[np].in(path[pr]+d[pr]);
            if(v[np].size()==0)
                dp[np]=0;
            else if(v[np].size()==1)
                dp[np]=*(--v[np].end());
            else
            {
                auto itt = (--v[np].end());
                dp[np]=*itt;
                itt--;
                dp[np]+=*itt;
            }
            dp[np]%=m;
            ans+=dp[np];
            ans%=m;
            if(v[np].size())
                path[np]=*(--v[np].end());
        }
        cans
    }
}

• Subtask 1: 0 / 11
• Subtask 2: 0 / 13
• Subtask 3: 0 / 31
• Subtask 4: 0 / 45