Parquet

Description:

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.

Sample Input:

2 6 2 2 1

Sample Output:

aabcca
aabdda

Sample Input:

1 1 100 100 100

Sample Output:

IMPOSSIBLE

Sample Input:

4 4 10 10 10

Sample Output:

aabb
aabb
bbaa
bbaa