#include <iostream>
#include <iomanip>
#include <string>
#include <cstring>
#include <cstdlib>
#include <cmath>

using namespace std;
long long a[8][8][100010], m;

int main()
{
    int n, n1, ch, ch1, l = 0, r = 0, u = 0, d = 0, l1, r1, u1, d1, ans = 1;
    string s;
    getline(cin, s);
    cin >> m;
    for (int i = 0; i < 8; i++)
        for (int j = 0; j < 8; j++)
            a[i][j][m] = 0;
    ch = s[0] - 96;
    n = s[1] - 48;
    ch1 = s[3]- 96;
    n1 = s[4] - 48;
    l1 = ch;
    r1 = 7 - l1;
    d1 = n;
    u1 = 7 - d1;
    int tt;
    for (int i = 1; i <= m; i++){
        tt = 8;
        if (l1 == i)
            l = 1;
        if (r1 == i)
            r = 1;
        if (u1 == i)
            u = 1;
        if (d1 == i)
            d = 1;
        if (l)
            tt -= 3;
        if (r)
            tt -= 3;
        if (u)
            tt -= 3;
        if (d)
            tt -= 3;
        if (l && u)
            tt++;
        if (l && d)
            tt++;
        if (r && u)
            tt++;
        if (r && d)
            tt++;
        ans *= tt;
    }
    //cout << ch << " " << n << endl;
    //cin >> tt;
    a[ch - 1][n - 1][m] = 1;
    for (int k = m; k > 0; k--)
        for (int x = 0; x < 8; x++)
            for (int y = 0; y < 8; y++){
                if (x > 0)
                    a[x - 1][y][k - 1] += a[x][y][k];
                if (x < 7)
                    a[x + 1][y][k - 1] += a[x][y][k];
                if (y > 0)
                    a[x][y - 1][k - 1] += a[x][y][k];
                if (y < 7)
                    a[x][y + 1][k - 1] += a[x][y][k];
                if (x > 0 && y > 0)
                    a[x - 1][y - 1][k - 1] += a[x][y][k];
                if (x > 0 && y < 7)
                    a[x - 1][y + 1][k - 1] += a[x][y][k];
                if (x < 7 && y > 0)
                    a[x + 1][y - 1][k - 1] += a[x][y][k];
                if (x < 7 && y < 7)
                    a[x + 1][y + 1][k - 1] += a[x][y][k];
                //cout << x << " " << y << " " << k << endl;
            }
    long long ff = a[ch1 - 1][n1 - 1][0];
    //cout << ff << " " << ans << endl;
    cout << setprecision(6) << fixed << ff * 1.0 / ans << endl;
    return 0;
}
/*
a1 b2
1
*/