ziyiliao/encryption

A solution to solve the encryption

Encryption

A solution to solve the encryption

Definition

An English text needs to be encrypted using the following encryption scheme. First, the spaces are removed from the text. Let be the length of this text. Then, characters are written into a grid, whose rows and columns have the following constraints:

For example, the sentence

s = if man was meant to stay on the ground god would have given us roots, after removing spaces is 54 characters long. SQRT(54) is between 7 and 8, so it is written in the form of a grid with 7 rows and 8 columns.

    ifmanwas  
    meanttos          
    tayonthe  
    groundgo  
    dwouldha  
    vegivenu  
    sroots

the output is

    imtgdvs fearwer mayoogo anouuio ntnnlvt wttddes aohghn sseoau

Constraint

• 1 <= s <= 81

• s is comprised only of characters in the range ascii[a-z].

Solution

This requires me to place the sentence in the R x C matrix by row, but print out by column. Using math, we can know that it just needs to print out the letters by skipping R letters.

The full solution script is provided here

Sample Case

Sample Input 1

haveaniceday

Sample Output 1

hae and via ecy

Explanation 1

L = 12, SQRT(12) is between 3 and 4. Rewritten with 3 rows and 4 columns:

have
anic
eday

Sample Input 2

feedthedog    

Sample Output 2

fto ehg ee dd

Explanation 2

L = 10, SQRT(10) is between 3 and 4. Rewritten with 3 rows and 4 columns:

feed
thed
og

Sample Input 3

chillout

Sample Output 3

clu hlt io

Explanation 3

L = 8, SQRT(8) is between 2 and 3. Rewritten with 3 columns and 3 rows (2*3 = 6 < 8 so we have to use 3x3)

chi
llo
ut

Sample Input 4

""

Sample Output 4

""

Explanation 4

Empty String

Sample Input 5

aaaaaabbbbbbccccccddddddeeeeee

Sample Output 5

abcde abcde abcde abcde abcde abcde 

Explanation 5

L = 30, SQRT(30) is between 5 and 6. Rewritten with 5 columns and 6 rows

abcde 
abcde 
abcde 
abcde 
abcde 
abcde 

Sample Input 6

aaaaaabbbbbbccccccddddddeeeee

Sample Output 6

abcde abcde abcde abcde abcde abcd

Explanation 6

L = 29, SQRT(29) is between 5 and 6. Rewritten with 5 columns and 6 rows

abcde 
abcde 
abcde 
abcde 
abcde 
abcd

Sample Input 7

aaaaaabbbbbbccccccddddddeeeeee

Sample Output 7

abcde abcde abcde abcde abcde abcdef

Explanation 7

L = 31, SQRT(30) is between 5 and 6. Rewritten with 6 columns and 6 rows

abcdef
abcde 
abcde 
abcde 
abcde 
abcde