#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <string>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <iomanip>
#include <utility>
#include <tuple>
#include <functional>
#include <bitset>
#include <cassert>
#include <complex>
#include <stdio.h>
#include <time.h>
#include <numeric>
#include <random>
#include <unordered_map>
#include <unordered_set>
#define all(a) a.begin(),a.end()
#define rep(i, n) for (ll i = 0; i < (n); i++)
#define pb push_back
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<ll, ll> P;
typedef complex<ld> com;
constexpr int inf = 1000000010;
constexpr ll INF = 1000000000000000010;
constexpr ld eps = 1e-12;
constexpr ld pi = 3.141592653589793238;
template<class T, class U> inline bool chmax(T &a, const U &b) { if (a < b) { a = b; return true; } return false; }
template<class T, class U> inline bool chmin(T &a, const U &b) { if (a > b) { a = b; return true; } return false; }


signed main() {
	cin.tie(0);
	ios::sync_with_stdio(false);
	cout << fixed << setprecision(20);

	int n, m, a, b;
	cin >> n >> m >> a >> b;
	vector<vector<char>> ans(n, vector<char>(m, '.'));
	bool flag = false;
	if (n >= 3 && m >= 3 && n % 2 == 1 && m % 2 == 1 && a % 2 != m / 2 % 2) {
		for (int i = 0; i < n - 3; i += 2) {
			if (b > 0) {
				ans[i][m - 1] = '^'; ans[i + 1][m - 1] = 'v'; b--;
			}
		}
		for (int j = 0; j < m - 3; j += 2) {
			if (a > 0) {
				ans[n - 1][j] = '<'; ans[n - 1][j + 1] = '>'; a--;
			}
		}
		if (a > 0) {
			ans[n - 3][m - 2] = '<'; ans[n - 3][m - 1] = '>'; a--;
		}
		if (a > 0) {
			ans[n - 1][m - 3] = '<'; ans[n - 1][m - 2] = '>'; a--;
		}
		if (b > 0) {
			ans[n - 2][m - 1] = '^'; ans[n - 1][m - 1] = 'v'; b--;
		}
		if (b > 0) {
			ans[n - 3][m - 3] = '^'; ans[n - 2][m - 3] = 'v'; b--;
		}
		flag = true;
	}
	else {
		if (m % 2 != 0) {
			for (int i = 0; i < n - 1; i += 2) {
				if (b > 0) {
					ans[i][m - 1] = '^'; ans[i + 1][m - 1] = 'v'; b--;
				}
			}
		}
		if (n % 2 != 0) {
			for (int j = 0; j < m - 1; j += 2) {
				if (a > 0) {
					ans[n - 1][j] = '<'; ans[n - 1][j + 1] = '>'; a--;
				}
			}
		}
	}
	for (int i = 0; i < n - 1; i += 2) {
		for (int j = 0; j < m - 1; j += 2) {
			if (flag && i == n - 3 && j == m - 3) continue;
			if (a > 0) {
				ans[i][j] = '<'; ans[i][j + 1] = '>'; a--;
				if (a > 0) {
					ans[i + 1][j] = '<'; ans[i + 1][j + 1] = '>'; a--;
				}
			}
			else if (b > 0) {
				ans[i][j] = '^'; ans[i + 1][j] = 'v'; b--;
				if (b > 0) {
					ans[i][j + 1] = '^'; ans[i + 1][j + 1] = 'v'; b--;
				}
			}
		}
	}
	if (a > 0 || b > 0) cout << "NO\n";
	else {
		cout << "YES\n";
		rep(i, n) {
			rep(j, m) cout << ans[i][j];
			cout << '\n';
		}
	}
}