#ifndef BZ
#pragma GCC optimize "-O3"
#endif
#include <bits/stdc++.h>

#define FASTIO

#ifdef FASTIO
#define scanf abacaba
#define printf abacaba
#endif

typedef long long ll;
typedef long long llong;
typedef long double ld;
typedef unsigned long long ull;

using namespace std;


/*
ll pw(ll a, ll b) {
	ll ans = 1; while (b) {
		while (!(b & 1)) b >>= 1, a = (a * a) % MOD;
		ans = (ans * a) % MOD, --b;
	} return ans;
}
*/

int a, b;
int n, m;

void no() {
	cout << "NO\n";
	exit(0);
}

char ans[1200][1200];
void run(int fl = 0) {
	for (int i = 0; i + 1 < n; i += 2)
		for (int j = 0; j + 1 < m; j += 2) {
			if (fl && a == 1 && b == 1) {
				ans[i][j] = '<', ans[i][j + 1] = '>';
				ans[i + 1][j] = '^';
				ans[i + 2][j] = 'v';
				--a, --b;
			}
			else if (a >= 2) {
				ans[i][j] = '<', ans[i][j + 1] = '>';
				ans[i + 1][j] = '<', ans[i + 1][j + 1] = '>';
				a -= 2;
			}
			else if (b >= 2) {
				ans[i][j] = '^';
				ans[i + 1][j] = 'v';
				ans[i][j + 1] = '^';
				ans[i + 1][j + 1] = 'v';
				b -= 2;
			}
			else if (a == 1) {
				ans[i][j] = '<', ans[i][j + 1] = '>';
				a -= 1;
			}
			else if (b == 1) {
				ans[i][j] = '^';
				ans[i + 1][j] = 'v';
				b -= 1;
			}
		}
}

int main() {
#ifdef FASTIO
	ios_base::sync_with_stdio(false), cin.tie(0), cout.tie(0);
#endif
	cin >> n >> m >> a >> b;
	for (int i = 0; i < n; ++i)
		for (int j = 0; j < m; ++j)
			ans[i][j] = '.';
	if (2 * (a + b) > n * m) {
		no();
	}
	if (a > (m / 2) * n)
		no();
	if (b > (n / 2) * m)
		no();
	if (a + b == (n * m) / 2) {
		if (n % 2 == 0 && m % 2 == 0) {
			if (a % 2 == 1)
				no();
			run();
		}
		else if (n % 2 == 0) {
			if (a % 2 == 1)
				no();
			int now = 0;
			while (now + 1 < n && b)
				ans[now][m - 1] = '^', ans[now + 1][m - 1] = 'v', now += 2, --b;
			run();
		}
		else if (m % 2 == 0) {
			if (b % 2 == 1)
				no();
			int now = 0;
			while (now + 1 < m && a)
				ans[n - 1][now] = '<', ans[n - 1][now + 1] = '>', now += 2, --a;
			run();
		}
		else {
			if (a) {
				ans[n - 1][m - 1] = '>';
				ans[n - 1][m - 2] = '<';
				--a;
			}
			int now = 0;
			while (now + 1 < m - 2 && a)
				ans[n - 1][now] = '<', ans[n - 1][now + 1] = '>', now += 2, --a;
			now = 0;
			while (now + 1 < n && b)
				ans[now][m - 1] = '^', ans[now + 1][m - 1] = 'v', now += 2, --b;
			run(1);
		}
	}
	else {
		if (n % 2 == 1) {
			int now = 0;
			while (now + 1 < m && a)
				ans[n - 1][now] = '<', ans[n - 1][now + 1] = '>', now += 2, --a;
		}
		if (m % 2 == 1) {
			int now = 0;
			while (now + 1 < n && b)
				ans[now][m - 1] = '^', ans[now + 1][m - 1] = 'v', now += 2, --b;
		}
		run();
	}
	cout << "YES\n";
	for (int i = 0; i < n; ++i)
		cout << ans[i] << "\n";
	return 0;
}


