| 1 | package rotate_image_48 |
| 2 | |
| 3 | func rotate(matrix [][]int) { |
| 4 | // transpose the matrix in-place, by turning it's rows into columns |
| 5 | for i := 0; i < len(matrix); i++ { |
| 6 | for j := i; j < len(matrix[i]); j++ { |
| 7 | matrix[i][j], matrix[j][i] = matrix[j][i], matrix[i][j] |
| 8 | } |
| 9 | } |
| 10 | |
| 11 | // reverse each row of the transposed matrix to get the 90deg rotated matrix |
| 12 | for i := 0; i < len(matrix); i++ { |
| 13 | for j := 0; j < len(matrix[i])/2; j++ { |
| 14 | matrix[i][j], matrix[i][len(matrix[i])-1-j] = |
| 15 | matrix[i][len(matrix[i])-1-j], matrix[i][j] |
| 16 | } |
| 17 | } |
| 18 | } |