#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#include <bits/stdc++.h>
#define dbg(x) cerr<<#x": "<<x<<"\n"
using namespace std;

const int N = 10005;

int i, j, n, a[N], s, m, b[N];
set<int> dp[N / 2];

void solve() {
	for(int i = 1; i <= n; i++)
		 cin >> a[i] >> b[i], s += a[i];

	int tot = n * m;

  dp[0].insert(0);
  for(i = 1; i <= n; ++i)
    for(j = min(n / 2 - 1, i); j >= 0; --j)
      for(auto it : dp[j])
        dp[j + 1].insert(it + a[i]);

  // dbg(s);
  int req = s / 2;

  if(dp[n / 2].lower_bound(req) == dp[n / 2].end()) {
  	cout << "Nu stiu ce fac aici :P\n";
  }
  int has1 = *dp[n / 2].lower_bound(req);
  // dbg(has1);
  if(2 * has1 == tot / 2) {
  	cout << "No solution\n";
  	return;
  }
  int has2 = s - has1;
  int half = tot / 2;
  double p;
  // dbg(has1);
  // dbg(has2);
  if(2 * s >= tot)
  	cout << "W ";
  else
  	cout << "B ",
  	has1 = half - has1,
  	has2 = half - has2;

  p = min(1. * has1 / half, 1. * has2 / half);;
  cout << p * 100 << '\n';
 }

void reset() {
	for(int i = 0; i <= N/2; i++)
		dp[i].clear();
	s = 0;
}

int main() {
	cout << fixed << setprecision(2);
  // citesc a[i] de la 1 la n
 	freopen("d.in", "r", stdin);

	cin >> n >> m;
	while(!cin.eof()) {
		reset();
		solve();
		cin >> n >> m;
	}

  return 0;
}