import std;

// AC: 263 ms
void calc1(int n) {
    // 2^17 > 100_000
    for (int i = 0; i < n-1; i++) {
        write('a');
        for (int j = 0; j < 17; j++) {
            if (i & (1 << j)) write('a');
            else write('b');
        }
        writeln('a');
    }
    writeln("an");
}

// AC: 23 ms
void calc2(int n) {
    auto cs = lowercase;
    // 26^4 > 100_000
    foreach (a, b, c, d; cartesianProduct(cs, cs, cs, cs).take(n-1)) {
        writeln('a', a, b, c, d, 'a');
    }
    writeln("an");
}

void main() {
    int n; scan(n);
    calc2(n);
}

void scan(T...)(ref T a) {
    string[] ss = readln.split;
    foreach (i, t; T) a[i] = ss[i].to!t;
}
T read(T)() { return readln.chomp.to!T; }
T[] reads(T)() { return readln.split.to!(T[]); }
alias readint = read!int;
alias readints = reads!int;