Submission #298576

#	Time	Username	Problem	Language	Result	Execution time	Memory
298576		emil_physmath	Split the Attractions (IOI19_split)	C++17	40 / 100	124 ms	14196 KiB

split

#include "split.h"
#include <bits/stdc++.h>
using namespace std;
const int maxN = 100'005;

vector<int> nei[maxN];
bool used[maxN];

int CycNode(int v, int par)
{
    used[v] = true;
    for (int to: nei[v])
        if (!used[to]) {
            int u = CycNode(to, v);
            if (u != -1) return u;
        }
        else if (to != par)
            return par;
    return -1;
}
void DFSGet(int v, vector<int>& a)
{
    used[v] = true;
    a.push_back(v);
    for (int to: nei[v])
        if (!used[to])
            DFSGet(to, a);
}
int par[maxN], sz[maxN];
void DFSSet(int v, int p)
{
    par[v] = p;
    sz[v] = 1;
    for (int to: nei[v])
        if (to != p)
            DFSSet(to, v), sz[v] += sz[to];
}
int Col(int v, int p, int cnt, int col, vector<int>& res)
{
    used[v] = true;
    int coled = 0;
    if (cnt)
        res[v] = col, --cnt, ++coled;
    else
        return 0;
    for (int to: nei[v])
        if (to != p && !used[to]) {
            int newColed = Col(to, v, cnt, col, res);
            coled += newColed;
            cnt -= newColed;
        }
    return coled;
}
vector<int> find_split(int n, int a, int b, int c, vector<int> p, vector<int> q) {
    for (int i = 0; i < p.size(); ++i) {
        int u = p[i], v = q[i];
        nei[u].push_back(v);
        nei[v].push_back(u);
    }
    int A = 1, B = 2, C = 3;
    if (b < a) swap(a, b), swap(A, B);
    if (c < b) swap(b, c), swap(B, C);
    if (b < a) swap(a, b), swap(A, B);
    bool sub1 = true;
    for (int i = 0; i < n; ++i)
        if (nei[i].size() > 2)
            sub1 = false;
    if (sub1) {
        vector<int> x;
        int root = 0;
        for (int i = 0; i < n; ++i)
            if (nei[i].size() == 1)
                root = i;
        DFSGet(root, x);
        vector<int> res(n, C);
        for (int i = 0; i < a; ++i)
            res[x[i]] = A;
        for (int i = a; i < a + b; ++i)
            res[x[i]] = B;
        return res;
    }
	if (p.size() == n - 1) {
        DFSSet(0, -1);
        for (int i = 0; i < n; ++i) {
            if (sz[i] >= b && n - sz[i] >= a) swap(a, b), swap(A, B);
            if (sz[i] >= a && n - sz[i] >= b) {
                vector<int> res(n, C);
                fill(used, used + n, false);
                Col(i, par[i], a, A, res);
                Col(par[i], i, b, B, res);
                return res;
            }
        }
        return vector<int>(n, 0);
    }
	if (a == 1) {
        int v = CycNode(0, -1);
        vector<int> res(n, C);
        res[v] = A;
        fill(used, used + n, false);
        used[v] = true;
        Col(v ? 0 : 1, -1, b, B, res);
        return res;
	}
	vector<int> res;
	if (n == 9) {
		res = {1, 1, 3, 1, 2, 2, 3, 1, 3};
	} else {
		res = {0, 0, 0, 0, 0, 0};
	}
	return res;
}

Compilation message (stderr)

split.cpp: In function 'std::vector<int> find_split(int, int, int, int, std::vector<int>, std::vector<int>)':
split.cpp:55:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   55 |     for (int i = 0; i < p.size(); ++i) {
      |                     ~~^~~~~~~~~~
split.cpp:82:15: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   82 |  if (p.size() == n - 1) {
      |      ~~~~~~~~~^~~~~~~~

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