Coloring

input/code.cpp: In function 'void dfs(int)':
input/code.cpp:12:25: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   12 |         if (g[s].size() < lim) return;
      |             ~~~~~~~~~~~~^~~~~

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

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

int lim = 0;

void dfs(int s) {
	if (col[s]) return;
	if (g[s].size() < lim) return;
	int seen[7] {};
	for (int u : g[s]) {
		seen[col[u]]++;
	}
	col[s] = 1;
	while (col[s] <= 6 && seen[col[s]]) col[s]++;
	if (col[s] > 6) assert(false);
	for (int u : g[s]) {
		dfs(u);
	}
}

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);
	}

	lim = 6;
	for (int i = 0; i < n; ++i) {
		dfs(i);
	}
	lim = 0;
	for (int i = 0; i < n; ++i) {
		dfs(i);
	}

	for (int i = 0; i < n; ++i) {
		cout << col[i] << " ";
	}
	cout << endl;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

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: RUNTIME ERROR

code: input/code.cpp:19: void dfs(int): Assertion `false' failed.

Test 17

Verdict: ACCEPTED

Test 18

Verdict: ACCEPTED

Test 19

Verdict: ACCEPTED

Test 20

Verdict: ACCEPTED

Test 21

Verdict: ACCEPTED

Test 22

Verdict: ACCEPTED

Test 23

Verdict: ACCEPTED

Test 24

Verdict: ACCEPTED

Test 25

Verdict: ACCEPTED

Test 26

Verdict: ACCEPTED

Test 27

Verdict: ACCEPTED