//#pragma GCC optimize ("O3")
//#pragma GCC target ("tune=native")
//#pragma GCC target ("avx")
//#include <bits/stdc++.h>
#include <algorithm>
#include <climits>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <ctime>
#include <iostream>
#include <sstream>
#include <functional>
#include <map>
#include <set>
#include <unordered_map>
#include <unordered_set>
#include <bitset>
#include <string>
#include <cstring>
#include <vector>
#include <queue>
#include <stack>
#include <deque>
#include <list>
#include <numeric>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<ll,ll> P;
typedef pair<P,ll> PPI;
typedef pair<ll,P> PIP;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<P> vp;
#define PQ(T) priority_queue<T,vector<T>,greater<T>>
#define PQ2(T) priority_queue<T>
const double PI = 3.14159265358979323846;
const double EPS = 1e-12;
const ll INF = 1LL<<29;
const ll mod = 1e9+7;
#define REP(i,a,b) for(ll (i)=a;(i)<(ll)(b);++(i))
#define rep(i,n) REP(i,0,n)
#define rep1(i,n) REP(i,1,n+1)
#define repd(i,n,d) for(ll (i)=0;(i)<(ll)(n);(i)+=(d))
#define all(v) (v).begin(), (v).end()
#define pb(x) push_back(x)
#define mp(x,y) make_pair((x),(y))
#define mset(m,v) memset((m),(v),sizeof(m))
#define chmin(x,y) ((x)=min((x),(y)))
#define chmax(x,y) ((x)=max((x),(y)))
#define fst first
#define snd second
#define UNIQUE(x) (x).erase(unique(all(x)),(x).end())
#define DEBUG(x) cerr<<"line ("<<__LINE__<<")  "<<#x<<": "<<x<<endl;
template<class T> ostream &operator<<(ostream &os, const vector<T> &v){int n=v.size();rep(i,n)os<<v[i]<<(i==n-1?"":" ");return os;}
#define INIT std::ios::sync_with_stdio(false);std::cin.tie(0);

ll h, w, a, b;
#define N 1005
string s[N];

void solve(){
	if((h*w<(a+b)*2)||(h==1&&b>0)||(w==1&&a>0)){
		cout<<"NO"<<endl;
		return;
	}
	ll h2 = h, w2 = w;
	rep(i, h2) s[i] = string(w, '.');
	if(a+b==0){
		cout<<"YES"<<endl;
		rep(i, h2) cout<<s[i]<<endl;
		return ;
	}
	if(h2%2&&w2%2){
		ll a2 = max(0LL, a-w2/2), b2 = max(0LL, b-h2/2);
		int t = (a2%2)&&(b2%2);
		if(b2%2) t = 1;
		for(int j = 0; j+1<w2; j+=2){
			if(a){
				s[h2-1][j] = '<';
				s[h2-1][j+1] = '>';
				a--;
			}
		}
		for(int i = h2-1; i-1>=0; i-=2){
			if(b){
				s[i][w2-1] = 'v';
				s[i-1][w2-1] = '^';
				b--;
			}
		}
		if(t){
			if(a){
				s[0][w2-2] = '<';
				s[0][w2-1] = '>';
				a--;
			}
			if(b){
				s[0][w2-3] = '^';
				s[1][w2-3] = 'v';
				b--;
			}
		}
		h2--; w2--;
		for(int i = 0; i+1<h2; i+=2){
			for(int j = 0; j+1<w2; j+=2){
				if(t&&(i==0)&&(j>=w2-2)) continue;
				if(a){
					s[i][j]='<';
					s[i][j+1]='>';
					a--;
					if(a){
						s[i+1][j]='<';
						s[i+1][j+1]='>';
						a--;
					}
				}
				else if(b){
					s[i][j]='^';
					s[i+1][j]='v';
					b--;
					if(b){
						s[i][j+1]='^';
						s[i+1][j+1]='v';
						b--;
					}
				}
			}
		}
	} else {
		if(h2%2){
			for(int j = 0; j+1<w2; j+=2){
				if(a){
					s[h2-1][j] = '<';
					s[h2-1][j+1] = '>';
					a--;
				}
			}
			h2--;
		} else if(w2%2){
			for(int i = h2-1; i-1>=0; i-=2){
				if(b){
					s[i][w2-1] = 'v';
					s[i-1][w2-1] = '^';
					b--;
				}
			}
			w2--;
		}
		for(int i = 0; i+1<h2; i+=2){
			for(int j = 0; j+1<w2; j+=2){
				if(a){
					s[i][j]='<';
					s[i][j+1]='>';
					a--;
					if(a){
						s[i+1][j]='<';
						s[i+1][j+1]='>';
						a--;
					}
				}
				else if(b){
					s[i][j]='^';
					s[i+1][j]='v';
					b--;
					if(b){
						s[i][j+1]='^';
						s[i+1][j+1]='v';
						b--;
					}
				}
			}
		}
	}
	if(a||b){
		cout<<"NO"<<endl;
		return;
	} else {
		cout<<"YES"<<endl;
		rep(i, h) cout<<s[i]<<endl;
	}
}

int main(){
	cin>>h>>w>>a>>b;
	solve();
	return 0;
}


Measured memory_bytes: 2304