#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#define x first
#define y second
#define pb push_back
#define mp make_pair
#define all(v) v.begin(),v.end()
#define sz(v) (int)v.size()
#define up_b upper_bound
#define low_b lower_bound
#define nl '\n'
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef long double ld;
typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update>ordered_set;
const int N=5e3+11;
const int M=1e6+1;
const ll inf=1e9+11;
const ld EPS=1e-6;
const ll INF=1e18;
const ll mod=/*999999001*/1e9+7;
const int dx[4]={1,0,0,-1};
const int dy[4]={0,1,-1,0};
int a[N][N];
int x,y;
int dfs(int i,int j){
if(x==i&&y==j){
return 0;
}
if(a[i][j]<0||a[i][j]>3)return inf;
return dfs(i+dx[a[i][j]],j+dy[a[i][j]])+1;
}
void solve(){
int n,m;
cin>>n>>m;
for(int i=1;i<=n;i++){
for(int j=1;j<=m;j++){
char c;
cin>>c;
if(c=='x')x=i,y=j;
if(c=='<')a[i][j]=2;
else if(c=='>')a[i][j]=1;
else if(c=='v')a[i][j]=0;
else if(c=='^')a[i][j]=3;
else if(c=='o')a[i][j]=4;
else a[i][j]=-1;
}
}
int mn=inf;
char ans=0;
for(int i=1;i<=n;i++){
for(int j=1;j<=m;j++){
if(a[i][j]==4){
if(j<m){
if(dfs(i,j+1)<mn){
mn=dfs(i,j+1);
ans='E';
}
}
if(i>1){
if(dfs(i-1,j)<mn){
mn=dfs(i-1,j);
ans='N';
}
}
if(i<n){
if(dfs(i+1,j)<mn){
mn=dfs(i+1,j);
ans='S';
}
}
if(j>1){
if(dfs(i,j-1)<mn){
mn=dfs(i,j-1);
ans='W';
}
}
if(mn==inf)cout<<":(";
else cout<<":)\n"<<ans;
return ;
}
}
}
}
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0),cout.tie(0);
int T=1;
//cin>>T;
for(int i=1;i<=T;i++){
solve();
cout<<nl;
}
return 0;
}
