import std.stdio, std.string, std.conv;
import std.range, std.algorithm, std.array, std.typecons, std.container;
import std.math, std.numeric, core.bitop;

enum inf = 1_001_001_001;
enum inf6 = 1_001_001_001_001_001_001L;
enum mod = 1_000_000_007L;

void main() {
    auto N = readln.chomp.map!(ch => ch - '0').array;
    auto L = N.length.to!int;

    debug {
        writeln(N);
    }

    int K;
    scan(K);

    auto dp = new long[][][](L + 1, 2, K + 2);
    dp[0][0][0] = 1;
    
    foreach (i ; 0 .. L) {
        foreach (j ; 0 .. 2) {
            foreach (x ; 0 .. K + 2) {
                foreach (d ; 0 .. (j ? 9 : N[i]) + 1) {
                    if (x == K + 1) {
                        dp[i + 1][j | (d < N[i])][x] += dp[i][j][x];
                    }
                    else {
                        dp[i + 1][j | (d < N[i])][x + (d != 0)] += dp[i][j][x];
                    }
                }
            }
        }
    }

    auto ans = dp[L][0][K] + dp[L][1][K];
    writeln(ans);
}










void scan(T...)(ref T args) {
    import std.stdio : readln;
    import std.algorithm : splitter;
    import std.conv : to;
    import std.range.primitives;

    auto line = readln().splitter();
    foreach (ref arg; args) {
        arg = line.front.to!(typeof(arg));
        line.popFront();
    }
    assert(line.empty);
}

void fillAll(R, T)(ref R arr, T value) {
    static if (is(typeof(arr[] = value))) {
        arr[] = value;
    }
    else {
        foreach (ref e; arr) {
            fillAll(e, value);
        }
    }
}

bool chmin(T, U...)(ref T x, U args) {
    bool isChanged;

    foreach (arg; args) {
        if (x > arg) {
            x = arg;
            isChanged = true;
        }
    }

    return isChanged;
}

bool chmax(T, U...)(ref T x, U args) {
    bool isChanged;

    foreach (arg; args) {
        if (x < arg) {
            x = arg;
            isChanged = true;
        }
    }

    return isChanged;
}
