import std.stdio; import std.array; import std.string; import std.conv; import std.algorithm; import std.typecons; import std.range; void main() { int N = readln().chomp.to!int; bool[string] used; foreach (i; iota(N)) used[readln().chomp] = true; string s1 = "ieau"; string s2 = "nbmgr"; auto p1 = [0, 1, 2, 2, 3, 3]; do { auto p2 = [0, 1, 2, 3, 4]; do { string s3 = ""; foreach (i; iota(5)) { s3 ~= s2[p2[i]]; s3 ~= s1[p1[i]]; } foreach (i; iota(11)) { if (!(s3[0..i]~s1[p1[5]]~s3[i..$] in used)) { writeln(s3[0..i]~s1[p1[5]]~s3[i..$]); return; } } } while(nextPermutation(p2)); } while(nextPermutation(p1)); writeln("NO"); }