| 11 | ) |
| 12 | |
| 13 | func Encrypt(text string, rails int) string { |
| 14 | if rails == 1 { |
| 15 | return text |
| 16 | } |
| 17 | |
| 18 | // Create a matrix for the rail fence pattern |
| 19 | matrix := make([][]rune, rails) |
| 20 | for i := range matrix { |
| 21 | matrix[i] = make([]rune, len(text)) |
| 22 | } |
| 23 | |
| 24 | // Fill the matrix |
| 25 | dirDown := false |
| 26 | row, col := 0, 0 |
| 27 | for _, char := range text { |
| 28 | if row == 0 || row == rails-1 { |
| 29 | dirDown = !dirDown |
| 30 | } |
| 31 | matrix[row][col] = char |
| 32 | col++ |
| 33 | if dirDown { |
| 34 | row++ |
| 35 | } else { |
| 36 | row-- |
| 37 | } |
| 38 | } |
| 39 | var result strings.Builder |
| 40 | for _, line := range matrix { |
| 41 | for _, char := range line { |
| 42 | if char != 0 { |
| 43 | result.WriteRune(char) |
| 44 | } |
| 45 | } |
| 46 | } |
| 47 | |
| 48 | return result.String() |
| 49 | } |
| 50 | func Decrypt(cipherText string, rails int) string { |
| 51 | if rails == 1 || rails >= len(cipherText) { |
| 52 | return cipherText |