#include <bits/stdc++.h>
using namespace std;
#define int long long
#define endl '\n'
#define pii pair<int, int>
const int sz = 105;
const int dx[] = {1, -1, 0, 0};
const int dy[] = {0, 0, 1, -1};
const int dc[] = {'S', 'N', 'E', 'W'};
int S, T, U, V;
char a[sz][sz];
int d[sz][sz];
int n, m;
bool valid(int x, int y){
return (x >= 1 && x <= n && y >= 1 && y <= m);
}
int get(char c){
if(c == '<'){
return 3;
}
if(c == '>'){
return 2;
}
if(c == '^'){
return 1;
}
return 0;
}
int bfs(int x, int y){
deque<pii> q;
memset(d, 63, sizeof d);
q.push_front({x, y});
d[x][y] = 0;
while(q.size()){
int x, y;
tie(x, y) = q.front();
q.pop_front();
if(x == U && y == V){
break;
}
if(a[x][y] == '.'){
continue;
}
int i = get(a[x][y]);
int u = x + dx[i];
int v = y + dy[i];
if(valid(u, v) && d[x][y] + 1 < d[u][v]){
d[u][v] = d[x][y] + 1;
q.push_back({u, v});
}
}
return d[U][V];
}
int32_t main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
// freopen("main.inp","r",stdin);
// freopen("main.out","w",stdout);
cin>>n>>m;
for(int i=1; i<=n; ++i){
for(int j=1; j<=m; ++j){
cin>>a[i][j];
if(a[i][j] == 'o'){
S = i;
T = j;
}
if(a[i][j] == 'x'){
U = i;
V = j;
}
}
}
vector<pair<int, char>> ans;
for(int i=0; i<4; ++i){
int u = S + dx[i];
int v = T + dy[i];
if(valid(u, v)){
int t = bfs(u, v);
ans.push_back({t, dc[i]});
}
}
sort(ans.begin(), ans.end());
if(ans[0].first != d[0][0]){
cout<<":)"<<endl<<ans[0].second;
}
else{
cout<<":(";
}
return 0;
}
