Codeforces 510 A.Fox and Snake

题目链接：http://codeforces.com/contest/510/problem/A

A. Fox And Snake
time limit per test2 seconds
memory limit per test256 megabytes

inputstandard input
outputstandard output

Fox Ciel starts to learn programming. The first task is drawing a fox! However, that turns out to be too hard for a beginner, so she decides to draw a snake instead.

A snake is a pattern on a n by m table. Denote c-th cell of r-th row as (r, c). The tail of the snake is located at (1, 1), then it's body extends to (1, m), then goes down 2 rows to (3, m), then goes left to (3, 1) and so on.

Your task is to draw this snake for Fox Ciel: the empty cells should be represented as dot characters ('.') and the snake cells should be filled with number signs ('#').

Consider sample tests in order to understand the snake pattern.

Input
The only line contains two integers: n and m (3 ≤ n, m ≤ 50).

n is an odd number.

Output
Output n lines. Each line should contain a string consisting of m characters. Do not output spaces.

Sample test(s)
input
3 3
output
###
..#
###
input
3 4
output
####
...#
####
input
5 3
output
###
..#
###
#..
###
input
9 9
output
#########
........#
#########
#........
#########
........#
#########
#........
#########

#include <iostream>

using namespace std;

int main()
{
    int m,n;
    cin>>m>>n;
    for(int i=1; i<=m; i++)
    {
        if(i % 2 ==1)
        {
            for(int j=1; j<=n; j++)
                cout<<"#";
            cout<<endl;
        }
        else
        {
            if(i % 4 == 2)
            {
                for(int j=1; j<n; j++)
                    cout<<".";
                cout<<"#"<<endl;
            }
            if(i % 4 == 0)
            {
                cout<<"#";
                for(int j=1; j<n; j++)
                    cout<<".";
                cout<<endl;
            }
        }
    }
    return 0;
}