#include <bits/stdc++.h>
using namespace std;
int main() {
  int N, M;
  cin >> N >> M;
  set<char> colors;
  for (int i = 0; i < N; i++) {
    char temp;
    for (int q = 0; q < M; q++) {
      cin >> temp;
      colors.insert(temp);
    }
  }
  if (colors.size() == 1) {
    auto it = colors.begin();
    if (*it == 'W' || *it == 'B' || *it == 'G') {
      cout << "#Black&White" << endl;
    } else
      cout << "#Color" << endl;
    return 0;
  }
  if (colors.size() <= 3) {
    for (auto it = colors.begin(); it != colors.end(); it++) {
      if (*it != 'W' && *it != 'B' && *it != 'G') {
        cout << "#Color" << endl;
        return 0;
      }
    }
    cout << "#Black&White" << endl;
    return 0;
  } else
    cout << "#Color" << endl;
  return 0;
}
