#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pll pair<ll,ll>
#define pii pair<int,int>
#define fs first
#define sc second
#define tlll tuple<ll,ll,ll>
const int mxn = 110;
string arr[mxn];
int N,M;
vector<pair<int,char>> ans;
pii dir[] = {{0,1},{0,-1},{1,0},{-1,0}};
string dd = "EWSN";
bitset<mxn> vis[mxn];
pii s,e;
int mv(int r,int c){
for(auto &i:vis)i.reset();
int re = 1;
while(r != e.fs||c != e.sc){
if(vis[r][c])return -1;
vis[r][c] = true;
re++;
if(arr[r][c] == '>')c++;
else if(arr[r][c] == '<')c--;
else if(arr[r][c] == '^')r--;
else if(arr[r][c] == 'v')r++;
else return -1;
}
return re;
}
int main(){
ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
cin>>N>>M;
for(int i = 0;i<N;i++){
cin>>arr[i];
for(int j = 0;j<M;j++){
if(arr[i][j] == 'o')s = pii(i,j);
else if(arr[i][j] == 'x')e = pii(i,j);
}
}
for(int i = 0;i<4;i++){
int len = mv(dir[i].fs+s.fs,dir[i].sc+s.sc);
if(len != -1)ans.push_back(make_pair(len,dd[i]));
}
sort(ans.begin(),ans.end());
if(ans.empty()){
cout<<":(\n";
return 0;
}
else{
cout<<":)\n"<<ans[0].sc<<'\n';
}
return 0;
}
