Submission #422751

#	Time	Username	Problem	Language	Result	Execution time	Memory
422751		oleh1421	Split the Attractions (IOI19_split)	C++17	40 / 100	158 ms	29716 KiB

split

//#include "grader.cpp"
#include "split.h"
#include <bits/stdc++.h>
typedef long long ll;
using namespace std;
const int N=200010;
vector<int>g[N],t[N];
pair<int,int>gr[3];
int sz[N];
int P[N];
bool used[N];
int timer=0;
int tin[N],fup[N];
void dfs(int v,int pr){
    sz[v]=1;
    tin[v]=fup[v]=++timer;
    P[v]=pr;
    used[v]=true;
    for (int to:g[v]){
        if (!used[to]){
            t[v].push_back(to);
            t[to].push_back(v);
            dfs(to,v);
            sz[v]+=sz[to];
            fup[v]=min(fup[v],fup[to]);
        } else if (to!=pr) fup[v]=min(fup[v],tin[to]);
    }
}
int ans[N];
bool allowed[N];
void Mark(int v,int ind){
    if (!gr[ind].first) return;
    gr[ind].first--;
    ans[v]=gr[ind].second;
//    if (!ind) cout<<"OK "<<v<<" "<<gr[ind].first<<" "<<gr[ind].second<<endl;
    for (int to:t[v]){
        if (ans[to]) continue;
        Mark(to,ind);
    }
}
void dfs1(int v,int pr){
    allowed[v]=true;
    for (int to:t[v]){
        if (to!=pr){
            dfs1(to,v);
        }
    }
}
void Mark1(int v,int ind){
    if (!gr[ind].first) return;
    gr[ind].first--;
    ans[v]=gr[ind].second;
//    if (!ind) cout<<"OK "<<v<<" "<<gr[ind].first<<" "<<gr[ind].second<<endl;
    for (int to:g[v]){
        if (ans[to] || !allowed[to]) continue;
        Mark1(to,ind);
    }
}
bool DONE=false;
vector<int> find_split(int n, int a, int b, int c, vector<int> p, vector<int> q) {
    gr[0]={a,1};
    gr[1]={b,2};
    gr[2]={c,3};
    sort(gr,gr+3);
	for (int i=0;i<p.size();i++){
        g[p[i]].push_back(q[i]);
        g[q[i]].push_back(p[i]);
	}
    dfs(0,-1);
    for (int i=0;i<n;i++) allowed[i]=true;
    for (int i=0;i<n;i++){
        if (sz[i]>=gr[0].first && sz[i]<=n-gr[0].first){
            if (sz[i]<=n-gr[1].first){
                ans[P[i]]=gr[1].second;
                ans[i]=gr[0].second;
                Mark(P[i],1);
                Mark(i,0);
            } else {
                ans[P[i]]=gr[0].first;
                ans[i]=gr[1].first;
                Mark(P[i],0);
                Mark(i,1);
            }
            DONE=true;
            break;
        }
    }
    if (!DONE){
        int V=-1;
        for (int i=0;i<n;i++){
            if (sz[i]<=n-gr[0].first) continue;
            if (V==-1 || sz[i]<sz[V]) V=i;
    //        if (sz[i]>=gr[0].first && sz[i]<=n-gr[0].first){
    //            if (sz[i]<=n-gr[1].first){
    //                ans[P[i]]=gr[1].second;
    //                ans[i]=gr[0].second;
    //                Mark(P[i],1);
    //                Mark(i,0);
    //            } else {
    //                ans[P[i]]=gr[0].first;
    //                ans[i]=gr[1].first;
    //                Mark(P[i],0);
    //                Mark(i,1);
    //            }
    //            DONE=true;
    //            break;
    //        }
        }
        for (int i=0;i<n;i++) allowed[i]=false;
        int cur=n-sz[V];
        vector<int>u;
        for (int to:t[V]){
            if (to==P[V]) continue;
            if (fup[to]<=tin[V]){
                cur+=sz[to];
                u.push_back(to);
                if (cur>=gr[0].first){
                    for (int i:u){
                        dfs1(i,V);
                    }
                    dfs1(P[V],V);
                    Mark1(P[V],0);
                    for (int i=0;i<n;i++) allowed[i]^=1;
                    Mark1(V,1);
                    DONE=true;
                    break;
                }
            }
        }
    }
//    x<=a
//    n-x
//        dfs1(0,-1);
    if (DONE){
        for (int i=0;i<n;i++){
            if (!ans[i]) ans[i]=gr[2].second;
        }
    }

	vector<int>res;
	for (int i=0;i<n;i++) res.push_back(ans[i]);
	return res;
}
/**
9 9 3 3 3
0 1
0 2
2 3
2 4
2 5
2 6
2 7
2 8
8 0

9 10
4 2 3
0 1
0 2
0 3
0 4
0 6
0 8
1 7
3 7
4 5
5 6


*/

Compilation message (stderr)

split.cpp: In function 'std::vector<int> find_split(int, int, int, int, std::vector<int>, std::vector<int>)':
split.cpp:65:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   65 |  for (int i=0;i<p.size();i++){
      |               ~^~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 11 / 11
• Subtask 3: 22 / 22
• Subtask 4: 0 / 24
• Subtask 5: 0 / 36