import core.bitop, std.algorithm, std.ascii, std.bigint, std.conv, std.math,
    std.functional, std.numeric, std.range, std.stdio, std.string, std.random,
    std.typecons, std.container, std.format;

// dfmt off
T lread(T = long)(){return readln.chomp.to!T();}
T[] lreads(T = long)(long n){return generate(()=>readln.chomp.to!T()).take(n).array();}
T[] aryread(T = long)(){return readln.split.to!(T[])();}
void scan(TList...)(ref TList Args){auto line = readln.split();
foreach (i, T; TList){T val = line[i].to!(T);Args[i] = val;}}
alias sread = () => readln.chomp();enum MOD = 10 ^^ 9 + 7;
alias PQueue(T, alias less = "a<b") = BinaryHeap!(Array!T, less);
// dfmt on

void main()
{
    long K = lread();

    long[] ans;
    void f(long l, long p)
    {
        // writefln("%s %s", l, p);
        if (l == 0)
        {
            ans ~= p;
            return;
        }
        if (p == -1)
        {
            foreach (i; 1 .. 10)
            {
                f(l - 1, i);
            }
            return;
        }
        long x = p % 10;
        f(l - 1, p * 10 + x);
        if (x != 0)
            f(l - 1, p * 10 + (x - 1));
        if (x != 9)
            f(l - 1, p * 10 + (x + 1));
    }

    foreach (i; 1 .. 11)
        f(i, -1);
    ans.sort();
    // writeln(ans[0 .. 30], ans.length);
    writeln(ans[K - 1]);
}
