Coloring

#include <bits/stdc++.h>
using namespace std;

#define all(x) x.begin(), x.end()

const int N = 2e5 + 1;
vector<int> g[N];
int col[N], inds[N];

int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);

	int n, m;
	cin >> n >> m;

	for (int i = 0; i < m; ++i) {
		int a, b;
		cin >> a >> b;
		a--;
		b--;
		g[a].push_back(b);
		g[b].push_back(a);
	}

	for (int i = 0; i < n; ++i) inds[i] = i;

	int seen[7] {};

	for (;;) {
		bool f = 0;

		for (int it = 0; it < n; ++it) {
			int i = inds[it];

			for (int j = 0; j < 7; ++j) seen[j] = 0;
			for (int j : g[i]) {
				seen[col[j]] = 1;
			}
			col[i] = 1;
			while (col[i] <= 6 && seen[col[i]]) col[i]++;
			if (col[i] > 6) { f = 1; break; }
		}

		if (!f) {
			for (int i = 0; i < n; ++i) cout << col[i] << " ";
			cout << endl;
			return 0;
		}
		random_shuffle(inds, inds + n);
	}
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: TIME LIMIT EXCEEDED

Test 4

Verdict: TIME LIMIT EXCEEDED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: TIME LIMIT EXCEEDED

Test 19

Verdict: TIME LIMIT EXCEEDED

Test 20

Verdict: TIME LIMIT EXCEEDED

Test 21

Verdict: TIME LIMIT EXCEEDED

Test 22

Verdict: TIME LIMIT EXCEEDED

Test 23

Verdict: TIME LIMIT EXCEEDED

Test 24

Verdict: ACCEPTED

Test 25

Verdict: ACCEPTED

Test 26

Verdict: ACCEPTED

Test 27

Verdict: ACCEPTED