Submission #710240

#	Time	Username	Problem	Language	Result	Execution time	Memory
710240		victor_gao	Designated Cities (JOI19_designated_cities)	C++17	100 / 100	498 ms	73724 KiB

designated_cities

//#pragma GCC optimize("Ofast,unroll-loops,O3")
//#pragma GCC optimize("avx,avx2,sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,fma,tune=native")
#include<bits/stdc++.h>
//#include<bits/extc++.h>
//#pragma pack(1)
#define fast ios::sync_with_stdio(0); cin.tie(0);
#define int long long
#define pii pair<int,int>
#define x first
#define y second
#define N 200015
using namespace std;
//using namespace __gnu_pbds;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
//typedef tree<int, null_type,less_equal<int>, rb_tree_tag,tree_order_statistics_node_update> order_multiset;
//typedef tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update> order_set;
int n,dp[N],ans[N],mx[N],len[N],pos[N],total=0,s;
int fa[N],cost[N],in[N],out[N],dep[N],t=0;
bool vis[N];
vector<pair<int,pii> >g[N];
vector<int>path;
void dfs1(int p,int lp){
    pos[p]=p;
    for (auto [i,c]:g[p]){
        if (i!=lp){
            dfs1(i,p);
            dp[p]=dp[p]+dp[i]+c.y;
            mx[p]=max(mx[p],mx[i]+c.x);
        }
    }
}
void dfs2(int p,int lp,int val){
    dp[p]=(dp[p]+dp[lp]+val);
    ans[1]=min(ans[1],total-dp[p]);
    if (ans[2]>total-dp[p]-len[p]){
        ans[2]=total-dp[p]-len[p];
        s=p;
    }
    for (auto [i,c]:g[p]){
        if (i!=lp){
            dp[p]=dp[p]-dp[i]-c.y;
            dfs2(i,p,c.x);
            dp[p]=dp[p]+dp[i]+c.y;
        }
    }
    dp[p]=(dp[p]-dp[lp]-val);
}
void dfs3(int p,int lp,int up){
    int mx1=0,mx2=0;
    len[p]=max(mx[p],up);
    for (auto [i,c]:g[p]){
        if (i!=lp){
            mx2=max(mx2,mx[i]+c.x);
            if (mx2>mx1) swap(mx1,mx2);
        }
    }
    for (auto [i,c]:g[p]){
        if (i!=lp){
            int use=(mx[i]+c.x==mx1) ? mx2 : mx1;
            dfs3(i,p,max(up,use)+c.y);
        }
    }
}
void dfs4(int p,int lp,int cs){
    cost[p]=cs; fa[p]=lp;
    in[p]=++t; dep[p]=dep[lp]+cs;
    path.push_back(p);
    for (auto [i,c]:g[p]){
        if (i!=lp)
            dfs4(i,p,c.x);
    }
    out[p]=t;
}
struct segtree{
    pii seg[4*N];
    int tag[4*N];
    void add_tag(int i,int val){  seg[i].x+=val; tag[i]+=val; }
    void push(int i){
        if (tag[i]){
            add_tag(2*i,tag[i]); add_tag(2*i+1,tag[i]);
            tag[i]=0;
        }
    }
    void build(int l,int r,int i){
        if (l==r){
            seg[i]={dep[path[l-1]],path[l-1]};
            return;
        }
        int mid=(l+r)>>1;
        build(l,mid,2*i); build(mid+1,r,2*i+1);
        seg[i]=max(seg[2*i],seg[2*i+1]);
    }
    void modify(int l,int r,int i,int ll,int rr,int val){
        if (ll<=l&&rr>=r){
            add_tag(i,val);
            return;
        }
        int mid=(l+r)>>1; push(i);
        if (rr<=mid) modify(l,mid,2*i,ll,rr,val);
        else if (ll>mid) modify(mid+1,r,2*i+1,ll,rr,val);
        else {
            modify(l,mid,2*i,ll,rr,val);
            modify(mid+1,r,2*i+1,ll,rr,val);
        }
        seg[i]=max(seg[2*i],seg[2*i+1]);
    }
}seg;
void walk(int a){
    while (!vis[a]){
        vis[a]=1;
        seg.modify(1,n,1,in[a],out[a],-cost[a]);
        a=fa[a];
    }
}
signed main(){
    fast
    cin>>n;
    for (int i=0;i<=n;i++)
        ans[i]=1e18;
    for (int i=1;i<n;i++){
        int a,b,c,d; cin>>a>>b>>c>>d;
        total=(total+c+d);
        g[a].push_back({b,{c,d}});
        g[b].push_back({a,{d,c}});
    }
    dfs1(1,0);
    dfs3(1,0,0);
    dfs2(1,0,0);
    dfs4(s,0,0);
    seg.build(1,n,1);
    vis[s]=1;
    for (int i=2;i<=n;i++){
        pii now=seg.seg[1];
        if (i>2) ans[i]=ans[i-1]-now.x;
        walk(now.y);
    }
    int q; cin>>q;
    while (q--){
        int c; cin>>c;
        cout<<ans[c]<<'\n';
    }
}

• Subtask 1: 6 / 6
• Subtask 2: 7 / 7
• Subtask 3: 9 / 9
• Subtask 4: 17 / 17
• Subtask 5: 17 / 17
• Subtask 6: 44 / 44