Fox And Snake · Interview Problem

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Codeforces

Easy

Arrays

Strings

Simulation

Fox And Snake

Print a fixed snake-like pattern of # characters on an n × m grid.

Acceptance 0%

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CF 510A

gfg

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Problem Statement

Problem

You are given two integers n and m. Print an n × m grid that looks like a snake:

Every row has exactly m characters.
Rows with an odd 1-based index are completely filled with #.
For even 1-based rows, place a single # at one end and dots . everywhere else.
The single # alternates between the right end and the left end on consecutive even rows.

This creates a continuous snake path when the rows are stacked together.

Task

Construct and print the grid exactly in the required format.

Input Format

A single line containing two integers n and m.

Output Format

Print n lines.
Each line must contain exactly m characters consisting only of # and ..

Constraints

1 ≤ n, m.
The grid dimensions are small enough to print directly.

Examples

Sample cases returned by the problem API.

Example 1

Input

3 3

Output

###
..#
###

Explanation

Row 1 is full. Row 2 has a single # on the right. Row 3 is full again.

Example 2

Input

4 5

Output

#####
....#
#####
#....

Explanation

Even rows alternate the position of the single # between the right and left ends.

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