#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <chrono>
#include <complex>
#include <cstdio>
#include <cstring>
#include <deque>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <list>
#include <map>
#include <memory>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <tuple>
#include <vector>
using namespace std;
#define int long long
#define all(x) begin(x), end(x)
#define sz(x) (int) (x).size()

const int mxn = 50;

int n, m, g[mxn+2][mxn+2];
vector<array<int,2>> src;

signed main() {
	ios::sync_with_stdio(false); cin.tie(nullptr);
	
	cin >> n >> m;
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= m; j++) {
			char c; cin >> c;
			if (c == '+') {
				src.push_back({i,j});
			}
			if (c == '\\') {
				g[i][j] = 1;
			}
			if (c == '/') {
				g[i][j] = 2;
			}
			if (c == '|') {
				g[i][j] = 3;
			}
			if (c == '-') {
				g[i][j] = 4;
			}
//			cout << g[i][j] << " ";
		}
//		cout << "\n";
	}
	
	int mx = 0;
	for (array<int,2> p : src) {
		int cx = p[0], cy = p[1];
		int x1, y1;
		//up
		int un = 0;
		x1 = cx, y1 = cy;
		while (g[x1-1][y1] == 3) {
			un++; x1--;
		}
		//down
		int dn = 0;
		x1 = cx, y1 = cy;
		while (g[x1+1][y1] == 3) {
			dn++; x1++;
		}
		//left
		int ln = 0;
		x1 = cx, y1 = cy;
		while (g[x1][y1-1] == 4) {
			ln++; y1--;
		}
		//rght
		int rn = 0;
		x1 = cx, y1 = cy;
		while (g[x1][y1+1] == 4) {
			rn++; y1++;
		}
		//northeast
		int nen = 0;
		x1 = cx, y1 = cy;
		while (g[x1-1][y1+1] == 2) {
			nen++; x1--; y1++;
		}
		//southeast
		int sen = 0;
		x1 = cx, y1 = cy;
		while (g[x1+1][y1+1] == 1) {
			sen++; x1++; y1++;
		}
		//southwest
		int swn = 0;
		x1 = cx, y1 = cy;
		while (g[x1+1][y1-1] == 2) {
			swn++; x1++; y1--;
		}
		//notrthweset
		int nwn = 0;
		x1 = cx, y1 = cy;
		while (g[x1-1][y1-1] == 1) {
			nwn++; x1--; y1--;
		}
		
//		cout << cx << " " << cy << ":\n" << un << " " << dn << " " << ln << " " << rn << "\n";
//		cout << nen << " " << sen << " " << swn << " " << nwn << "\n\n";
		
		vector<int> val = {un,dn,ln,rn,nen,sen,swn,nwn};
		int mnv = 1e18;
		for (auto i : val) {
			mnv = min(mnv, i);
		}
		
		mx = max(mx, mnv);
		
	}
	cout << mx;
	
	return 0;
}