#include <bits/stdc++.h>

using namespace std;

#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define RFOR(i, a, b) for (int i = (a) - 1; i >= (b); i--)
#define FILL(a, b) memset(a, b, sizeof(a))
#define SZ(a) int(a.size())
#define ALL(a) a.begin(), a.end()
#define PB push_back
#define MP make_pair
#define F first
#define S second

typedef long long LL;
typedef vector<int> VI;
typedef pair<int, int> PII;
typedef double db;

void solve()
{
	int n, k;
	cin >> n >> k;
	unordered_set<int> s;
	s.reserve(4 * k);
	FOR (i, 0, k) s.insert(i + 1);
	VI l(n), r(n);
	VI ans(n);
	vector<PII> v;
	set<PII> m;
	FOR (i, 0, n)
	{
		cin >> l[i] >> r[i];
		v.PB({l[i], (i + 1)});
		v.PB({r[i], -(i + 1)});
	}
	sort(ALL(v));
	int res = 0;
	int p = 0;
	FOR (i, 0, 2 * n)
	{
		if (SZ(s) == 0) res += v[i].F - p;
		p = v[i].F;
		if (v[i].S < 0)
		{
			int j = abs(v[i].S) - 1;
			if (m.count(MP(v[i].F, ans[j])))
				s.insert(ans[j]);
			m.erase(MP(v[i].F, ans[j]));
		}
		else
		{
			int c = -1;
			int j = v[i].S - 1;	
			if (SZ(s))
			{
				c = *s.begin();
				s.erase(s.begin());
				m.insert({r[j], c});
			}			
			else
			{
				auto it = m.begin();
				c = it->S;
				int x = max(it->F, r[j]); 			
				m.erase(m.begin());
				m.insert({x, c});
			}	
			ans[j] = c;
		}
	}
	cout << res << '\n';
	FOR (i, 0, n)
	{
		cout << ans[i] << ' ';
	}
	cout << '\n';
}

int main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);
	int t;
	cin >> t;
	while (t--)
	{
		solve();
	}
}