Description：

Solution：

Code：

#include<algorithm>

#include<iostream>

#include<cstdlib>

#include<cstdio>

#include<cmath>

#include<cstring>

using namespace std;

int n,m;

#define MAXN 52

inline char getc()

{

	register char c = getchar();

	while(c != '*' && c != '.')c = getchar();

	return c;

}

typedef unsigned long long ll;

char p[MAXN][MAXN];

ll gcd(ll a,ll b){return (b == 0ull ? a : gcd(b,a % b));}

ll lcm(ll a,ll b){return a / gcd(a,b) * b;}

struct frac

{

	ll a,b;

	frac(){a = 0ull;b = 1ull;}

	frac friend operator + (frac x,frac y)

	{

		frac res;

		ll t = gcd(x.b,y.b);

		res.a = (x.a * (y.b / t)) + (y.a * (x.b / t));

		res.b = x.b / t * y.b;

		return res;

	}

	frac friend operator / (frac x,ll k)

	{

		ll t = gcd(x.a,k);

		x.a /= t;x.b *= k / t;

		return x;

	}

	void set(){a = 1ull;b = 1ull;return;}

};

frac f[MAXN][MAXN];

void pt(frac k)

{

	cout << k.a << "/" << k.b << endl;

	return;

}

int main()

{

	scanf("%d%d",&n,&m);

	for(int i = 1;i <= n;++i)

	{

		for(int j = 1;j <= i;++j)

		{

			p[i][j] = getc();

		}

	}

	f[1][1].set();

	++n;

	for(int i = 2;i <= n;++i)

	{

		for(int j = 1;j <= i;++j)

		{

			if(j > 1 && p[i - 1][j - 1] == '*')f[i][j] = f[i][j] + (f[i - 1][j - 1] / 2ull);

			if(j < i && p[i - 1][j] == '*')f[i][j] = f[i][j] + (f[i - 1][j] / 2ull);

			if(i > 2 && j > 1 && p[i - 2][j - 1] == '.')f[i][j] = f[i][j] + f[i - 2][j - 1];

		}

	}

	++m;

	pt(f[n][m]);

	return 0;

}