#include<iostream>
#include<algorithm>
#include<vector>
#include<string>
#include<set>
#include<queue>
#include<stack>
#include<bitset>
using namespace std;
int p = 1000000007;
#define int long long
#define vel vector<long long>
#define vvel vector<vel>
#define rep(i,n) for(long long i=0;i<n;i++)
#define sor(v) sort(v.begin(),v.end())
#define mmax(a,b) a=max(a,b)
#define mmin(a,b) a=min(a,b)
#define mkp make_pair
#define pin pair<int,int>
#define V vector
#define Endl endl
#define veb vector<bool>
#define sq(a) (a)*(a)
#define rev(s) reverse(s.begin(),s.end())
#define end_pr(s) cout << s <<endl;return 0
#define itn int
int kai_size = 1000001;
vel kai(kai_size, 1);
vel ink(kai_size, 1);
vel dist;
int RE() {
	vel v(3, 2);
	return v.at(4); 
}
int ru(int a, int r) {
	if (r == 0) { return 1; }
	int ans = ru(a, r / 2);
	ans *= ans; ans %= p;
	if (r % 2 == 1) { ans *= a; }
	return ans % p;
}
int inv(int a) {
	return ru(a, p - 2);
}
void make_kai() {
	rep(i, kai_size-1) { kai[i + 1] = (kai[i] * (i + 1)) % p; }
	rep(i, kai_size) { ink[i] = inv(kai[i]); }
}
int com(int n, int r) {
	if (r < 0 || n < r) { return 0; }
	int ans = kai[n] * ink[r];
	ans %= p; ans *= ink[n - r]; ans %= p;
	return ans;
}
vel dis(int mid1, vvel &way) {
	int n = way.size();
	vel dist(n, -1); dist[mid1] = 0;
	queue<int> q;
	q.push(mid1);
	while (!q.empty()) {
		int st = q.front(); q.pop();
		rep(i, way[st].size()) {
			int to = way[st][i];
			if (dist[to] == -1) {
				dist[to] = dist[st] + 1;
				q.push(to);
			}
		}
	}
	return dist;
}
pin most_far(int now, int n, vvel &way) {
	vel dist1 = dis(now, way);
	pin ans = mkp(-1, 0);
	rep(i, n) {
		if (dist1[i] > ans.first) { ans = mkp(dist1[i], i); }
	}
	return ans;
}

int per(int a, int b) {
	int ans = a % b;
	if (ans < 0) { ans += b; }
	return ans;
}
vel uni(vel &v) {
	sor(v);
	vel ans(1, v[0]);
	for (int i = 1; i < v.size(); i++) {
		if (v[i] != v[i-1]) { ans.push_back(v[i]); }
	}
	v = ans;
	return v;
}
int s_gcd(int a, int b) {
	if (b == 0) { return a; }
	return s_gcd(b, a%b);
}
int gcd(int a, int b) {
	if (a < b) { swap(a, b); }
	return s_gcd(a, b);
}
bool is_prime(int i) {
	for (int j = 2; j*j <= i; j++) {
		if (i%j == 0) { return false; }
	}
	return true;
}
int get(int i, int j, vvel &ans) {
	int n = ans.size();
	if (i < 0 || n <= i || j < 0 || n <= j) { return 1; }
	return ans[i][j];
}
int lcm(int a, int b) {
	return a * b / gcd(a, b);
}
bool solve0(int a, int b, int n, int m, V<V<char>> &ans) {
	if ((a + 1) / 2 + (b + 1) / 2 > (n*m)/ 4) { return false; }
	else {
		rep(i, b / 2) {
			int y = (i * 2) / m;
			int x = i % (m / 2);
			ans[2 * y][2 * x] = '^';
			ans[2 * y][2 * x + 1] = '^';
			ans[2 * y + 1][2 * x] = 'v';
			ans[2 * y + 1][2 * x + 1] = 'v';
		}
		if (b % 2 == 1) {
			int y = ((b / 2) * 2) / m;
			int x = (b / 2) % (m / 2);
			ans[2 * y][2 * x] = '^';
			ans[2 * y + 1][2 * x] = 'v';
		}
		int st = (b + 1) / 2;
		for (int i = st; i < st + (a / 2); i++) {
			int y = (i * 2) / m;
			int x = i % (m / 2);
			ans[2 * y][2 * x] = '<';
			ans[2 * y][2 * x + 1] = '>';
			ans[2 * y + 1][2 * x] = '<';
			ans[2 * y + 1][2 * x + 1] = '>';
		}
		if (a % 2 == 1) {
			st += a / 2;
			int y = (st * 2) / m;
			int x = st % (m / 2);
			ans[2 * y][2 * x] = '<';
			ans[2 * y][2 * x + 1] = '>';
		}
	}
	return true;
}
bool solve1(int a, int b, int n, int m, V<V<char>> &ans) {
	rep(i, min(b, n / 2)) {
		ans[2 * i][m - 1] = '^';
		ans[2 * i + 1][m - 1] = 'v';
	}
	b -= min(b, n / 2); m--;
	return solve0(a, b, n, m, ans);
}
bool solve2(int a, int b, int n, int m, V<V<char>> &ans) {
	rep(i, min(a, m / 2)) {
		ans[n - 1][2 * i] = '<';
		ans[n - 1][2 * i + 1] = '>';
	}
	a -= min(a, m / 2); n--;
	return solve0(a, b, n, m, ans);
}
bool solve3(int a, int b, int n, int m, V<V<char>> &ans) {
	if (n == 1) { return solve2(a, b, n, m - 1, ans); }
	if (m == 1) { return solve1(a, b, n - 1, m, ans); }
	if (2 * a + 2 * b + 1 > n*m) { return false; }
	if (a % 2 == (m / 2) % 2||n*m-2*a-2*b-1>0) {
		rep(i, min(a, m / 2)) {
			ans[n - 1][2 * i] = '<';
			ans[n - 1][2 * i + 1] = '>';
		}
		a -= min(a, m / 2); n--;
		return solve1(a, b, n, m, ans);
	}
	if (b * 2 < n || a * 2 < m) { return false; }
	ans[n - 1][m - 2] = '<';
	ans[n - 1][m - 1] = '>';
	ans[n - 2][m - 3] = '^';
	ans[n - 1][m - 3] = 'v';
	ans[n - 3][m - 3] = '<';
	ans[n - 3][m - 2] = '>';
	ans[n - 3][m - 1] = '^';
	ans[n - 2][m - 1] = 'v';
	rep(i,(m-3) / 2) {
		ans[n - 1][2 * i] = '<';
		ans[n - 1][2 * i + 1] = '>';
	}
	a -= (m +1) / 2;
	rep(i, (n-3) / 2) {
		ans[2 * i][m - 1] = '^';
		ans[2 * i + 1][m - 1] = 'v';
	}
	b -= (n +1) / 2;
	n--; m--;
	solve0(a, b, n, m, ans);
	return true;
}
signed main() {
	int n, m; int a, b; cin >> n >> m >> a >> b;
	vector<vector<char>> ans(n,vector<char>(m,'.'));
	if (n % 2 == 0 and m % 2 == 0) {
		if (!solve0(a, b, n, m, ans)) { end_pr("NO"); }
	}
	else if (n % 2 == 0) {
		if (!solve1(a, b, n, m, ans)) { end_pr("NO"); }
	}
	else if (m % 2 == 0) {
		if (!solve2(a, b, n, m, ans)) { end_pr("NO"); }
	}
	else {
		if (!solve3(a, b, n, m, ans)) { end_pr("NO"); }
	}
	cout << "YES" << endl;
	rep(i, n) {
		rep(j, m) {
			cout << ans[i][j];
		}
		cout << endl;
	}
	return 0;
}


Measured memory_bytes: 17920