#include <bits/stdc++.h>
using namespace std;
#define maxn 3392990


int r, c;

bool inrange(int x, int y){
    return 0 <= x && x < r && 0 <= y && y < c;
}

int char2dir(char c){
    switch(c){
        case '>':
            return 0;
        case '^':
            return 1;
        case '<':
            return 2;
        case 'v':
            return 3;
    }
    assert(false);
    return -1;
}

int di[4]= {0, -1, 0, 1};
int dj[4] = {1, 0, -1, 0};

struct pos{
    int x;
    int y;
    bool operator!=(const pos rhs) const{
        return x != rhs.x || y != rhs.y;
    }
};


int main() {
    
    cin >> r >> c;
    vector<vector<char> > m(r, vector<char>(c));
    //vector<vector<int>> status(r, vector<int>(c, 0));
    //vector<vector<int>> value(r, vector<int>(c, 0));
    for(int i = 0; i < r; ++i){
        for(int j = 0; j < c;++j){
            cin >> m[i][j];
            //if (m[i][j] == '.'|| m[i][j] == '#') status[i][j] = 2;
        }
    }
    int mval = -1;
    int curx = 0;
    int cury = 0;
    
    for(int i = 0; i < r; ++i){
        for(int j = 0; j < c;++j){
            int count = 0;
            vector<vector<bool> > visited(r, vector<bool>(c, false)); 
            vector<vector<bool> > visited2(r, vector<bool>(c, false));
            if (m[i][j] == '.'|| m[i][j] == '#') continue;
            pos cur = {i, j};
            while(inrange(cur.x, cur.y) && m[cur.x][cur.y] != '.' && m[cur.x][cur.y] != '#' && !visited2[cur.x][cur.y]){
                visited2[cur.x][cur.y]= true;
                for(int k = 0; k < 4; ++k){
                    int nx = cur.x + di[k]; 
                    int ny = cur.y+dj[k];
                    if(inrange(nx, ny) && m[nx][ny] == '#'){
                        visited[nx][ny] = true;
                    }
                }
                int dir = char2dir(m[cur.x][cur.y]);
                cur = {cur.x + di[dir], cur.y+ dj[dir]};
            } 
            for(int x = 0; x < r; ++x){
                for(int y = 0; y < c; ++y){
                    if(visited[x][y]){
                        ++count;
                    }
                }
            }
            if(count > mval){
                mval = count;
                curx = i;
                cury = j;
            }
        }
    } 
    cout << mval << '\n';
}