Submission #535417

#	Time	Username	Problem	Language	Result	Execution time	Memory
535417		mario05092929	Split the Attractions (IOI19_split)	C++14	100 / 100	288 ms	25112 KiB

split

#include "split.h"
#include <bits/stdc++.h>
#define x first
#define y second
using namespace std;
typedef long long ll;
typedef pair <int,int> pi;
typedef vector <int> vec;
vector <int> rv[100005];
vector <int> v[100005];
int n,m,A,B,C,a,b;
int cnt,cntmx;
int c[100005],sz[100005],p[100005],szp[100005];
int ch[100005],poham[100005];
pi po[3];
vector <int> ans;
vector <int> tv[100005];
vector <int> com,dfscom;

int Find(int x) {return (x == p[x] ? x : p[x] = Find(p[x]));}

void init_union() {
    for(int i = 0;i < n;i++) {
        p[i] = i, szp[i] = 1;
    }
}

int get_sz(int x,int pp) {
    sz[x] = 1;
    for(int i : tv[x]) {
        if(i == pp) continue;
        sz[x] += get_sz(i,x);
    }
    return sz[x];
}

int get_cent(int x,int pp,int cap) {
    for(int i : tv[x]) if(i != pp&&sz[i] > cap) return get_cent(i,x,cap);
    return x;
}

int make_cent() {
    return get_cent(0,-1,get_sz(0,-1)/2);
}

void dfs_fill(int x,int pp,int color) {
    if(cnt == cntmx||ans[x]) return;
    cnt++;
    ans[x] = color;
    for(int i : tv[x]) {
        if(i == pp) continue;
        dfs_fill(i,x,color);
    }
}

void dfs_pofill(int x,int color,int isok) {
    if(cnt == cntmx||ans[x]||poham[x] != isok) return;
    cnt++;
    ans[x] = color;
    for(int i : rv[x]) {
        dfs_pofill(i,color,isok);
    }
}

void canDo(int x,int wi) {
    cnt = 0, cntmx = a; dfs_fill(wi,x,po[0].y);
    cnt = 0, cntmx = b; dfs_fill(x,wi,po[1].y);
    for(int i = 0;i < n;i++) {
        if(!ans[i]) ans[i] = po[2].y;
    }
}

void merge(int x,int y) {
    if(Find(x) == Find(y)) return;
    x = Find(x), y = Find(y);
    p[x] = y;
    szp[y] += szp[x];
}

void dfs_union(int x,int pp) {
    for(int i : tv[x]) {
        if(i == pp) continue;
        merge(i,x);
        dfs_union(i,x);
    }
}

void dfs_com(int x) {
    if(c[x]) return;
    c[x] = 1;
    dfscom.push_back(x);
    for(int i : v[x]) dfs_com(i);
}

vec find_split(int N,int AA,int BB,int CC,vec vec1,vec vec2) {
    n = N, A = AA, B = BB, C = CC;
    m = vec1.size();
    po[0] = {A,1}, po[1] = {B,2}, po[2] = {C,3};
    sort(po,po+3);
    a = po[0].x, b = po[1].x;
    ans.resize(n,0);
    init_union();
    for(int i = 0;i < m;i++) {
        int x = vec1[i], y = vec2[i];
        rv[x].push_back(y);
        rv[y].push_back(x);
        if(Find(x) == Find(y)) continue;
        merge(x,y);
        tv[x].push_back(y);
        tv[y].push_back(x);
    }
    int cent = make_cent();
    get_sz(cent,-1);
    init_union();
    for(int i : tv[cent]) {
        dfs_union(i,cent);
        if(szp[Find(i)] >= a) {
            canDo(cent,i);
            return ans;
        }
    }
    for(int i = 0;i < m;i++) {
        if(vec1[i] == cent||vec2[i] == cent) continue;
        int x = vec1[i], y = vec2[i];
        if(Find(x) != Find(y)) {
            v[p[x]].push_back(p[y]);
            v[p[y]].push_back(p[x]);
        }
    }
    memset(c,0,sizeof(c));
    for(int i = 0;i < n;i++) {
        if(i == cent||Find(i) != i||c[i]) continue;
        dfscom.clear(), com.clear();
        dfs_com(i);
        int sum = 0;
        for(int j : dfscom) {
            sum += szp[j];
            com.push_back(j);
            if(sum >= a) break;
        }
        if(sum >= a) {
            int st = -1;
            for(int j : com) ch[j] = 1;
            for(int j = 0;j < n;j++) {
                if(ch[Find(j)]) {
                    poham[j] = 1;
                    st = j;
                }
            }
            cnt = 0, cntmx = a; dfs_pofill(st,po[0].y,1);
            cnt = 0, cntmx = b; dfs_pofill(cent,po[1].y,0);
            for(int j = 0;j < n;j++) {
                if(!ans[j]) ans[j] = po[2].y;
            }
            return ans;
        }
    }
    return ans;
}

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