1185

/*
状态压缩DP
采用1038的方法
*/

// include file
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <cctype>
#include <ctime>

#include <iostream>
#include <sstream>
#include <fstream>
#include <iomanip>
#include <bitset>

#include <algorithm>
#include <string>
#include <vector>
#include <queue>
#include <set>
#include <list>
#include <functional>

using namespace std;

// typedef
typedef long long LL;
typedef unsigned long long ULL;

// 
#define read freopen("in.txt","r",stdin)
#define write freopen("out.txt","w",stdout)
#define FORi(a,b,c) for(int i=(a);i<(b);i+=c)
#define FORj(a,b,c) for(int j=(a);j<(b);j+=c)
#define FORk(a,b,c) for(int k=(a);k<(b);k+=c)
#define FORp(a,b,c) for(int p=(a);p<(b);p+=c)
#define FORii(a,b,c) for(int ii=(a);ii<(b);ii+=c)
#define FORjj(a,b,c) for(int jj=(a);jj<(b);jj+=c)
#define FORkk(a,b,c) for(int kk=(a);kk<(b);kk+=c)

#define FF(i,a)    for(int i=0;i<(a);i++)
#define FFD(i,a)   for(int i=(a)-1;i>=0;i--)

#define Z(a) (a<<1)
#define Y(a) (a>>1)

const double eps = 1e-6;
const double INFf = 1e10;
const int INFi = 1000000000;
const double Pi = acos(-1.0);

template<class T> inline T sqr(T a){return a*a;}
template<class T> inline T TMAX(T x,T y)
{
	if(x>y) return x;
	return y;
}
template<class T> inline T TMIN(T x,T y)
{
	if(x<y) return x;
	return y;
}
template<class T> inline void SWAP(T &x,T &y)
{
	T t = x;
	x = y;
	y = t;
}
template<class T> inline T MMAX(T x,T y,T z)
{
	return TMAX(TMAX(x,y),z);
}


// code begin

int N,M;
char mp[110][12];
int dp[2][59050];
int prerow[12];
int currow[12];
int preten;
int curten;
int san[12];
int ret;
int tmp[5];

void Init()
{
	san[0] = 1;
	FORi(1,11,1)
		san[i] = san[i-1]*3;
}
void san2ten(int A[],int &ans)
{
	ans  = 0;
	FORi(0,M,1)
	{
		ans = ans*3+A[i];
	}
}
void ten2san(int ten,int A[])
{
	for(int i=M-1;i>=0;i--)
	{
		A[i] = ten%3;
		ten/=3;
	}
}

void dfs(int r,int c,int v,int cs)
{
	if(c>=M) 
	{
		dp[r&1][cs] = TMAX(dp[r&1][cs],dp[(r+1)&1][preten]+v);
		if(dp[r&1][cs]>ret)
			ret = dp[r&1][cs];
		return;
	}

	if( currow[c]==0 && prerow[c]==0 && mp[r][c]=='P' )
	{
		currow[c] = 2;
		cs += currow[c]*san[M-c-1];
		dfs(r,c+3,v+1,cs);
		cs -= currow[c]*san[M-c-1];
		currow[c] = 0;
	}
	dfs(r,c+1,v,cs);
}

int main()
{
	read;
	write;
	Init();
	while(scanf("%d %d",&N,&M)!=-1)
	{
		FORi(1,N+1,1)
		{
			scanf("%s",mp[i]);
		}
		
		// 0之前和现在都是0
		// 1当前是0,之前是1
		// 2当前是1
 
		FORi(0,M,1)
			prerow[i] = 0;
		preten = 0;
		memset(dp,-1,sizeof(dp));
		dp[0][preten] = 0;
		ret = 0;
		FORi(1,N+1,1)
		{
			memset(dp[i&1],-1,sizeof(dp[i&1]));
			FORj(0,san[M],1)
			{
				if( dp[(i+1)&1][j]==-1 )
					continue;

				ten2san(j,prerow);

				//
				FORk(0,M,1)
				{
					if(prerow[k]==2)
					{
						currow[k] = 1;
					}
					else if(prerow[k]==1)
					{
						currow[k] = 0;
					}
					else
						currow[k] = 0;
				}
				
				san2ten(currow,curten);
				preten = j;
				//
				dfs(i,0,0,curten);
			}

		}
		printf("%d\n",ret);
	}
	return 0;
}