Problem: Once Bob decided to lay a parquet floor in his living room. The living room is of size n × m metres. Bob had planks of three types: a planks 1 × 2 meters, b planks 2 × 1 meters, and c planks 2 × 2 meters. Help Bob find out, if it is possible to parquet the living room with such a set of planks, and if it is possible, find one of the possible ways to do so. Bob doesn't have to use all the planks.

Input

The first input line contains 5 space-separated integer numbers n, m, a, b, c (1 ≤ n, m ≤ 100, 0 ≤ a, b, c ≤ 104), n and m — the living room dimensions, a, b and c — amount of planks 1 × 2, 2 × 1 и 2 × 2 respectively. It's not allowed to turn the planks.

Output

If it is not possible to parquet the room with such a set of planks, output IMPOSSIBLE. Otherwise output one of the possible ways to parquet the room — output n lines with m lower-case Latin letters each. Two squares with common sides should contain the same letters, if they belong to one and the same plank, and different letters otherwise. Different planks can be marked with one and the same letter (see examples). If the answer is not unique, output any.

Examples

Input

2 6 2 2 1


Output

aabcca
aabdda


Input

1 1 100 100 100


Output

IMPOSSIBLE


Input

4 4 10 10 10


Output

aabb
aabb
bbaa
bbaa

Solution (in JAVA):

Solution:
import java.io.*;
import java.util.*;

import static java.lang.Math.*;
import static java.util.Arrays.fill;
import static java.util.Arrays.binarySearch;
import static java.util.Arrays.sort;

public class Main {
	public static void main(String[] args) throws IOException {
		try {
			if (new File("input.txt").exists())
				System.setIn(new FileInputStream("input.txt"));
		} catch (SecurityException e) {}
		
		new Main().run();
	}

	BufferedReader in;
	PrintWriter out;
	StringTokenizer st = new StringTokenizer("");
	
	int[][] map;
	
	int N;
	int M;
	int A;
	int B;
	int C;
	
	int block = 1;
	
	Map<Integer, Character> match;
	
	void run() throws IOException {
		in = new BufferedReader(new InputStreamReader(System.in));
		out = new PrintWriter(System.out);
		
		N = nextInt();
		M = nextInt();
		A = nextInt();
		B = nextInt();
		C = nextInt();
		
		if (N * M % 2 == 1) {
			out.println("IMPOSSIBLE");
			out.close();
			return;
		}
		
		map = new int [N][M];
		int n = N;
		int m = M;
		
		if (M % 2 == 1) {
			if (N / 2 > B) {
				out.println("IMPOSSIBLE");
				out.close();
				return;
			}
			for (int i = 0; i < N; i += 2)
				placeB(i, M - 1);
			m--;
		} else if (N % 2 == 1) {
			if (M / 2 > A) {
				out.println("IMPOSSIBLE");
				out.close();
				return;
			}
			for (int j = 0; j < M; j += 2)
				placeA(N - 1, j);
			n--;
		}
		
		try {
			for (int i = 0; i < n; i += 2) {
				for (int j = 0; j < m; j += 2) {
					place2x2(i, j);
				}
			}
		} catch (NoBlocksException e) {
			out.println("IMPOSSIBLE");
			out.close();
			return;
		}
		
		match = new HashMap<Integer, Character>();
		int[] used = new int [26];
		int tick = 1;
		
		for (int i = 0; i < N; i++) {
			for (int j = 0; j < M; j++) {
				if (!match.containsKey(map[i][j])) {
					tick++;
					for (int k = i - 1; k >= 0; k--) {
						if (match.containsKey(map[k][j])) {
							used[match.get(map[k][j]) - 'a'] = tick;
							break;
						}
					}
					if (j < M - 1)
					for (int k = i - 1; k >= 0; k--) {
						if (match.containsKey(map[k][j + 1])) {
							used[match.get(map[k][j + 1]) - 'a'] = tick;
							break;
						}
					}
					for (int k = i + 1; k < N; k++) {
						if (match.containsKey(map[k][j])) {
							used[match.get(map[k][j]) - 'a'] = tick;
							break;
						}
					}
					if (j < M - 1)
					for (int k = i + 1; k < N; k++) {
						if (match.containsKey(map[k][j + 1])) {
							used[match.get(map[k][j + 1]) - 'a'] = tick;
							break;
						}
					}
					for (int k = j - 1; k >= 0; k--) {
						if (match.containsKey(map[i][k])) {
							used[match.get(map[i][k]) - 'a'] = tick;
							break;
						}
					}
					if (i < N - 1)
					for (int k = j - 1; k >= 0; k--) {
						if (match.containsKey(map[i + 1][k])) {
							used[match.get(map[i + 1][k]) - 'a'] = tick;
							break;
						}
					}
					for (int k = j + 1; k < M; k++) {
						if (match.containsKey(map[i][k])) {
							used[match.get(map[i][k]) - 'a'] = tick;
							break;
						}
					}
					if (i < N - 1)
					for (int k = j + 1; k < M; k++) {
						if (match.containsKey(map[i + 1][k])) {
							used[match.get(map[i + 1][k]) - 'a'] = tick;
							break;
						}
					}
					for (int c = 0; c < 26; c++) {
						if (used[c] != tick) {
							match.put(map[i][j], (char)(c + 'a'));
							break;
						}
					}
				}
			}
		}
		
		for (int i = 0; i < N; i++) {
			for (int j = 0; j < M; j++) {
				out.print(match.get(map[i][j]));
			}
			out.println();
		}
		
		out.close();
	}
	
	void placeB(int i, int j) {
		map[i][j] = map[i + 1][j] = block++;
		B--;
	}

	void placeA(int i, int j) {
		map[i][j] = map[i][j + 1] = block++;
		A--;
	}
	
	void placeC(int i, int j) {
		map[i][j] = map[i][j + 1] = map[i + 1][j] = map[i + 1][j + 1] = block++;
		C--;
	}
	
	void place2x2(int i, int j) throws NoBlocksException {
		if (C > 0) {
			placeC(i, j);
		} else if (A >= 2) {
			placeA(i, j);
			placeA(i + 1, j);
		} else if (B >= 2) {
			placeB(i, j);
			placeB(i, j + 1);
		} else {
			throw new NoBlocksException();
		}
	}
	
	class NoBlocksException extends Throwable {
		private static final long serialVersionUID = -8940572594654972860L;
	}
	
	String nextToken() throws IOException {
		while (!st.hasMoreTokens())
			st = new StringTokenizer(in.readLine());
		return st.nextToken();
	}
	
	int nextInt() throws IOException {
		return Integer.parseInt(nextToken());
	}
	
	long nextLong() throws IOException {
		return Long.parseLong(nextToken());
	}
	
	double nextDouble() throws IOException {
		return Double.parseDouble(nextToken());
	}
	
	String nextLine() throws IOException {
		st = new StringTokenizer("");
		return in.readLine();
	}
	
	boolean EOF() throws IOException {
		while (!st.hasMoreTokens()) {
			String s = in.readLine();
			if (s == null)
				return true;
			st = new StringTokenizer(s);
		}
		return false;
	}
}