void main()
{
    long n, p;
    rdVals(n, p);
    string s = rdStr;

    long result;

    if (p == 2 || p == 5)
    {
        foreach (i, x; s)
        {
            if ((x - '0') % p) continue;
            result += i + 1;
        }
        result.writeln;
        return;
    }

    long[] exp = new long[n];
    exp[n-1] = 1;
    foreach_reverse (i; 0 .. n-1)
    {
        exp[i] = 10 * exp[i+1] % p;
    }
    long[] list = new long[p];
    long num = 0;
    foreach_reverse (i, x; s)
    {
        num = (num + (x - '0') * exp[i]) % p;
        ++list[num];
    }

    result += list[0];
    foreach (l; list)
    {
        result += (l * (l - 1)) >> 1;
    }

    result.writeln;
}

enum long mod = 10^^9 + 7;
enum long inf = 1L << 60;
enum double eps = 1.0e-9;

T rdElem(T = long)()
if (!is(T == struct))
{
    return readln.chomp.to!T;
}

alias rdStr = rdElem!string;
alias rdDchar = rdElem!(dchar[]);

T rdElem(T)()
if (is(T == struct))
{
    T result;
    string[] input = rdRow!string;
    assert(T.tupleof.length == input.length);
    foreach (i, ref x; result.tupleof)
    {
        x = input[i].to!(typeof(x));
    }
    return result;
}

T[] rdRow(T = long)()
{
    return readln.split.to!(T[]);
}

T[] rdCol(T = long)(long col)
{
    return iota(col).map!(x => rdElem!T).array;
}

T[][] rdMat(T = long)(long col)
{
    return iota(col).map!(x => rdRow!T).array;
}

void rdVals(T...)(ref T data)
{
    string[] input = rdRow!string;
    assert(data.length == input.length);
    foreach (i, ref x; data)
    {
        x = input[i].to!(typeof(x));
    }
}

void wrMat(T = long)(T[][] mat)
{
    foreach (row; mat)
    {
        foreach (j, compo; row)
        {
            compo.write;
            if (j == row.length - 1) writeln;
            else " ".write;
        }
    }
}

import std.stdio;
import std.string;
import std.array;
import std.conv;
import std.algorithm;
import std.range;
import std.math;
import std.numeric;
import std.mathspecial;
import std.traits;
import std.container;
import std.functional;
import std.typecons;
import std.ascii;
import std.uni;
import core.bitop;