#define _CRT_SECURE_NO_WARNINGS
#define _SCL_SECURE_NO_WARNINGS
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <string>
#include <vector>
#include <list>
#include <utility>
#include <algorithm>
#include <functional>
#include <cmath>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <iomanip>
#include <sstream>
#include <bitset>
#include <limits>
#include <numeric>
#include <valarray>
#include <fstream>

using namespace std;
typedef unsigned int uint;
typedef long long LL;
typedef unsigned long long ULL;
typedef pair<LL, LL> PP;
#define REP(i,a,n) for(LL i = (a); i < (LL)(n); ++i)
#define REM(i,a,n) for(LL i = ((n) - 1); i >= (a); --i)
#define FLOAT fixed << setprecision(16)
#define SPEEDUP {cin.tie(NULL); ios::sync_with_stdio(false);}
const int INF = 0x3FFFFFFF;
const LL INFLL = 0x3FFFFFFF3FFFFFFF;
const double INFD = 1.0e+308;
const string INFSTR = "\x7f";
const double EPS = 1.0e-9;

void YesNo(bool b) { cout << (b ? "Yes" : "No") << endl; }
void YESNO(bool b) { cout << (b ? "YES" : "NO") << endl; }
template <class T, class U>
istream& operator>>(istream& ist, pair<T, U>& right) { return ist >> right.first >> right.second; }
template <class T, class U>
ostream& operator<<(ostream& ost, const pair<T, U>& right) { return ost << right.first << ' ' << right.second; }
template <class T, class TCompatible, size_t N>
void Fill(T(&dest)[N], const TCompatible& val) { fill(dest, dest + N, val); }
template <class T, class TCompatible, size_t M, size_t N>
void Fill(T(&dest)[M][N], const TCompatible& val) { for (int i = 0; i < M; ++i) Fill(dest[i], val); }
template<class T>
T Compare(T left, T right) { return left > right ? 1 : (left < right ? -1 : 0); }
istream& Ignore(istream& ist) { string s; ist >> s; return ist; }
bool Inside(int i, int j, int h, int w) { return i >= 0 && i < h && j >= 0 && j < w; }
template <class ForwardIterator, class T>
bool All_of(ForwardIterator first, ForwardIterator last, const T& value) {
	for (; first < last; ++first) if (*first != value) return false; return true;
}
// all_of

#ifdef ONLY_MY_ENVIR
#include "IntMod.h"
#include "Union_Find.h"
#include "Graph.h"
#include "Range.h"
#include "Global.h"
#include "Flow_Solver.h"
#include "Tree.h"
#include "Suffix_Array.h"
#include "Geometry.h"
#include "Matrix.h"
#include "Segment_Tree.h"
#endif

#ifdef __GNUC__
typedef __int128 LLL;
istream& operator>> (istream& ist, __int128& val) { LL tmp;  ist >> tmp; val = tmp; return ist; }
ostream& operator<< (ostream& ost, __int128 val) { LL tmp = val; ost << tmp; return ost; }
#endif

#if 1234567891
#include <array>
#include <random>
#include <unordered_set>
#include <unordered_map>
template<typename T>
using PriorityQ = priority_queue<T, vector<T>, greater<T> >;	// コスト小を優先
#endif

int N, M, A, B;
char ans[1000][1001];

void Yoko(char s[][1001]) {
	s[0][0] = '<';
	s[0][1] = '>';
}

void Tate(char s[][1001]) {
	s[0][0] = '^';
	s[1][0] = 'v';
}


bool GuGu(char s[][1001], int H, int W, int p, int q) {
	if (2 * (p + q) > H * W) return false;
	if (2 * (p + q) == H * W && p % 2 == 1) return false;

	for (int i = 0; i < H; i += 2) {
		for (int j = 0; j < W; j += 2) {
			if (p > 0) {
				Yoko((char(*)[1001])&s[i][j]); --p;
				if (p > 0) {
					Yoko((char(*)[1001])&s[i + 1][j]); --p;
				}
			} else if (q > 0) {
				Tate((char(*)[1001])&s[i][j]); --q;
				if (q > 0) {
					Tate((char(*)[1001])&s[i][j + 1]); --q;
				}
			}
		}
	}

	return true;
}


bool GuKi(char s[][1001], int H, int W, int p, int q) {
	for (int i = 0; i < H; i += 2) {
		if (q > 0) {
			Tate((char(*)[1001])&s[i][0]); --q;
		}
	}

	return GuGu((char(*)[1001])&s[0][1], H, W - 1, p, q);
}

bool KiGu(char s[][1001], int H, int W, int p, int q) {
	for (int j = 0; j < W; j += 2) {
		if (p > 0) {
			Yoko((char(*)[1001])&s[0][j]); --p;
		}
	}

	return GuGu((char(*)[1001])&s[1][0], H - 1, W, p, q);
}

bool KiKi(char s[][1001], int H, int W, int pp, int qq) {
	int p = pp, q = qq;
	for (int i = 0; i < H - 1; i += 2) {
		if (q > 0) {
			Tate((char(*)[1001])&s[i][0]); --q;
		}
	}
	if (KiGu((char(*)[1001])&s[0][1], H, W - 1, p, q)) {
		return true;
	}
	Fill(ans, '.');
	//////////////////////////////////////////////////////
	p = pp; q = qq;
	for (int j = 0; j < W - 1; j += 2) {
		if (p > 0) {
			Yoko((char(*)[1001])&s[0][j]); --p;
		}
	}

	if (GuKi((char(*)[1001])&s[1][0], H - 1, W, p, q)) {
		return true;
	}
	Fill(ans, '.');
	//////////////////////////////////////////////////////
	p = pp; q = qq;
	if (p < 2 || q < 2) return false;

	Tate((char(*)[1001])&s[0][0]); --q;
	Tate((char(*)[1001])&s[1][2]); --q;
	Yoko((char(*)[1001])&s[0][1]); --p;
	Yoko((char(*)[1001])&s[2][0]); --p;

	int ql = q >= (H - 3) * 3 / 2 ? (H - 3) * 3 / 2 : q;
	int pl = (H - 3) * 3 / 2 - ql;
	return
		GuKi((char(*)[1001])&s[3][0], H - 3, 3, pl, ql) &&
		KiGu((char(*)[1001])&s[0][3], H, W - 3, p - pl, q - ql);
}



int main() {
	cin >> N >> M >> A >> B;
	Fill(ans, '.');
	bool ok;
	if (N % 2 == 0) {
		if (M % 2 == 0) {
			ok = GuGu(ans, N, M, A, B);
		} else {
			ok = GuKi(ans, N, M, A, B);
		}
	} else {
		if (M % 2 == 0) {
			ok = KiGu(ans, N, M, A, B);
		} else {
			ok = KiKi(ans, N, M, A, B);
		}
	}


	if (ok) {
		cout << "YES" << endl;
		REP(i, 0, N) {
			REP(j, 0, M) {
				printf("%c", ans[i][j]);
			}
			printf("\n");
		}
	} else {
		cout << "NO" << endl;
	}




	return 0;
}

Measured memory_bytes: 2304