import std.algorithm, std.conv, std.range, std.stdio, std.string;

void main()
{
  auto n = readln.chomp.to!size_t;
  auto si = n.iota.map!(_ => readln.chomp.s2l).array;

  si.sort();

  foreach (vi; vowels)
    foreach (ci; consonants)
      foreach (li; lines) {
        auto a = merge(vi, ci, li);
        if (!si.assumeSorted.contains(a)) {
          writeln(a.l2s);
          return;
        }
      }

  writeln("NO");
}

long merge(int[] vi, int[] ci, int[] li)
{
  return (vi ~ ci).indexed(li).di2l;
}

long di2l(R)(R di)
{
  auto l = 0L;
  foreach (d; di) {
    l *= 10;
    l += d;
  }
  return l;
}

long s2l(string s)
{
  return s.map!(c => c.predSwitch('i',1,'a',2,'e',3,'u',4,'n',5,'b',6,'m',7,'g',8,'r',9)).di2l;
}

string l2s(long l)
{
  int[] di;
  while (l > 0) {
    di = (l % 10) ~ di;
    l /= 10;
  }
  return di.map!(d => d.predSwitch(1,'i',2,'a',3,'e',4,'u',5,'n',6,'b',7,'m',8,'g',9,'r')).to!string;
}

auto vowels = [[1,2,2,3,4,4],[1,2,2,4,3,4],[1,2,2,4,4,3],[1,2,3,2,4,4],[1,2,3,4,2,4],[1,2,3,4,4,2],[1,2,4,2,3,4],[1,2,4,2,4,3],[1,2,4,3,2,4],[1,2,4,3,4,2],[1,2,4,4,2,3],[1,2,4,4,3,2],[1,3,2,2,4,4],[1,3,2,4,2,4],[1,3,2,4,4,2],[1,3,4,2,2,4],[1,3,4,2,4,2],[1,3,4,4,2,2],[1,4,2,2,3,4],[1,4,2,2,4,3],[1,4,2,3,2,4],[1,4,2,3,4,2],[1,4,2,4,2,3],[1,4,2,4,3,2],[1,4,3,2,2,4],[1,4,3,2,4,2],[1,4,3,4,2,2],[1,4,4,2,2,3],[1,4,4,2,3,2],[1,4,4,3,2,2],[2,1,2,3,4,4],[2,1,2,4,3,4],[2,1,2,4,4,3],[2,1,3,2,4,4],[2,1,3,4,2,4],[2,1,3,4,4,2],[2,1,4,2,3,4],[2,1,4,2,4,3],[2,1,4,3,2,4],[2,1,4,3,4,2],[2,1,4,4,2,3],[2,1,4,4,3,2],[2,2,1,3,4,4],[2,2,1,4,3,4],[2,2,1,4,4,3],[2,2,3,1,4,4],[2,2,3,4,1,4],[2,2,3,4,4,1],[2,2,4,1,3,4],[2,2,4,1,4,3],[2,2,4,3,1,4],[2,2,4,3,4,1],[2,2,4,4,1,3],[2,2,4,4,3,1],[2,3,1,2,4,4],[2,3,1,4,2,4],[2,3,1,4,4,2],[2,3,2,1,4,4],[2,3,2,4,1,4],[2,3,2,4,4,1],[2,3,4,1,2,4],[2,3,4,1,4,2],[2,3,4,2,1,4],[2,3,4,2,4,1],[2,3,4,4,1,2],[2,3,4,4,2,1],[2,4,1,2,3,4],[2,4,1,2,4,3],[2,4,1,3,2,4],[2,4,1,3,4,2],[2,4,1,4,2,3],[2,4,1,4,3,2],[2,4,2,1,3,4],[2,4,2,1,4,3],[2,4,2,3,1,4],[2,4,2,3,4,1],[2,4,2,4,1,3],[2,4,2,4,3,1],[2,4,3,1,2,4],[2,4,3,1,4,2],[2,4,3,2,1,4],[2,4,3,2,4,1],[2,4,3,4,1,2],[2,4,3,4,2,1],[2,4,4,1,2,3],[2,4,4,1,3,2],[2,4,4,2,1,3],[2,4,4,2,3,1],[2,4,4,3,1,2],[2,4,4,3,2,1],[3,1,2,2,4,4],[3,1,2,4,2,4],[3,1,2,4,4,2],[3,1,4,2,2,4],[3,1,4,2,4,2],[3,1,4,4,2,2],[3,2,1,2,4,4],[3,2,1,4,2,4],[3,2,1,4,4,2],[3,2,2,1,4,4],[3,2,2,4,1,4],[3,2,2,4,4,1],[3,2,4,1,2,4],[3,2,4,1,4,2],[3,2,4,2,1,4],[3,2,4,2,4,1],[3,2,4,4,1,2],[3,2,4,4,2,1],[3,4,1,2,2,4],[3,4,1,2,4,2],[3,4,1,4,2,2],[3,4,2,1,2,4],[3,4,2,1,4,2],[3,4,2,2,1,4],[3,4,2,2,4,1],[3,4,2,4,1,2],[3,4,2,4,2,1],[3,4,4,1,2,2],[3,4,4,2,1,2],[3,4,4,2,2,1],[4,1,2,2,3,4],[4,1,2,2,4,3],[4,1,2,3,2,4],[4,1,2,3,4,2],[4,1,2,4,2,3],[4,1,2,4,3,2],[4,1,3,2,2,4],[4,1,3,2,4,2],[4,1,3,4,2,2],[4,1,4,2,2,3],[4,1,4,2,3,2],[4,1,4,3,2,2],[4,2,1,2,3,4],[4,2,1,2,4,3],[4,2,1,3,2,4],[4,2,1,3,4,2],[4,2,1,4,2,3],[4,2,1,4,3,2],[4,2,2,1,3,4],[4,2,2,1,4,3],[4,2,2,3,1,4],[4,2,2,3,4,1],[4,2,2,4,1,3],[4,2,2,4,3,1],[4,2,3,1,2,4],[4,2,3,1,4,2],[4,2,3,2,1,4],[4,2,3,2,4,1],[4,2,3,4,1,2],[4,2,3,4,2,1],[4,2,4,1,2,3],[4,2,4,1,3,2],[4,2,4,2,1,3],[4,2,4,2,3,1],[4,2,4,3,1,2],[4,2,4,3,2,1],[4,3,1,2,2,4],[4,3,1,2,4,2],[4,3,1,4,2,2],[4,3,2,1,2,4],[4,3,2,1,4,2],[4,3,2,2,1,4],[4,3,2,2,4,1],[4,3,2,4,1,2],[4,3,2,4,2,1],[4,3,4,1,2,2],[4,3,4,2,1,2],[4,3,4,2,2,1],[4,4,1,2,2,3],[4,4,1,2,3,2],[4,4,1,3,2,2],[4,4,2,1,2,3],[4,4,2,1,3,2],[4,4,2,2,1,3],[4,4,2,2,3,1],[4,4,2,3,1,2],[4,4,2,3,2,1],[4,4,3,1,2,2],[4,4,3,2,1,2],[4,4,3,2,2,1]];

auto consonants = [[5,6,7,8,9],[5,6,7,9,8],[5,6,8,7,9],[5,6,8,9,7],[5,6,9,7,8],[5,6,9,8,7],[5,7,6,8,9],[5,7,6,9,8],[5,7,8,6,9],[5,7,8,9,6],[5,7,9,6,8],[5,7,9,8,6],[5,8,6,7,9],[5,8,6,9,7],[5,8,7,6,9],[5,8,7,9,6],[5,8,9,6,7],[5,8,9,7,6],[5,9,6,7,8],[5,9,6,8,7],[5,9,7,6,8],[5,9,7,8,6],[5,9,8,6,7],[5,9,8,7,6],[6,5,7,8,9],[6,5,7,9,8],[6,5,8,7,9],[6,5,8,9,7],[6,5,9,7,8],[6,5,9,8,7],[6,7,5,8,9],[6,7,5,9,8],[6,7,8,5,9],[6,7,8,9,5],[6,7,9,5,8],[6,7,9,8,5],[6,8,5,7,9],[6,8,5,9,7],[6,8,7,5,9],[6,8,7,9,5],[6,8,9,5,7],[6,8,9,7,5],[6,9,5,7,8],[6,9,5,8,7],[6,9,7,5,8],[6,9,7,8,5],[6,9,8,5,7],[6,9,8,7,5],[7,5,6,8,9],[7,5,6,9,8],[7,5,8,6,9],[7,5,8,9,6],[7,5,9,6,8],[7,5,9,8,6],[7,6,5,8,9],[7,6,5,9,8],[7,6,8,5,9],[7,6,8,9,5],[7,6,9,5,8],[7,6,9,8,5],[7,8,5,6,9],[7,8,5,9,6],[7,8,6,5,9],[7,8,6,9,5],[7,8,9,5,6],[7,8,9,6,5],[7,9,5,6,8],[7,9,5,8,6],[7,9,6,5,8],[7,9,6,8,5],[7,9,8,5,6],[7,9,8,6,5],[8,5,6,7,9],[8,5,6,9,7],[8,5,7,6,9],[8,5,7,9,6],[8,5,9,6,7],[8,5,9,7,6],[8,6,5,7,9],[8,6,5,9,7],[8,6,7,5,9],[8,6,7,9,5],[8,6,9,5,7],[8,6,9,7,5],[8,7,5,6,9],[8,7,5,9,6],[8,7,6,5,9],[8,7,6,9,5],[8,7,9,5,6],[8,7,9,6,5],[8,9,5,6,7],[8,9,5,7,6],[8,9,6,5,7],[8,9,6,7,5],[8,9,7,5,6],[8,9,7,6,5],[9,5,6,7,8],[9,5,6,8,7],[9,5,7,6,8],[9,5,7,8,6],[9,5,8,6,7],[9,5,8,7,6],[9,6,5,7,8],[9,6,5,8,7],[9,6,7,5,8],[9,6,7,8,5],[9,6,8,5,7],[9,6,8,7,5],[9,7,5,6,8],[9,7,5,8,6],[9,7,6,5,8],[9,7,6,8,5],[9,7,8,5,6],[9,7,8,6,5],[9,8,5,6,7],[9,8,5,7,6],[9,8,6,5,7],[9,8,6,7,5],[9,8,7,5,6],[9,8,7,6,5]];

auto lines = [[0,6,1,7,2,8,3,9,4,10,5],[6,0,1,7,2,8,3,9,4,10,5],[6,0,7,1,2,8,3,9,4,10,5],[6,0,7,1,8,2,3,9,4,10,5],[6,0,7,1,8,2,9,3,4,10,5],[6,0,7,1,8,2,9,3,10,4,5]];