*rotate Image

title :

You are given a n x n 2D matrix representing an image.

Rotate the image by degrees (clockwise).

Follow up:
Could do this in-place?

Problem Solving Ideas:

In-place Solution

By using the relation "matrix[i][j] = Matrix[n-1-j][i]", we can loop through the matrix.

The code is as follows:

1  Public voidRotateint[] matrix) {2     intn =matrix.length;3      for(inti = 0; I <N/2; i++) {4          for(intj = 0; J <Math.ceil (((double) n)/2.); J + +) {5             inttemp =Matrix[i][j];6MATRIX[I][J] = matrix[n-1-J] [i];7Matrix[n-1-j][i] = matrix[n-1-i][n-1-j];8MATRIX[N-1-I][N-1-J] = matrix[j][n-1-i];9Matrix[j][n-1-i] =temp;Ten         } One     } A}

A=math.ceil (((double) n)/2.  
If n=3, a=2.0;
If n=4, a=2.0;
If n=5, a=3.0;
If n=6, a=3.0;

Run the process:

Suppose the image is

After the rotation: 7,4,1

4,5,6 8,5,2

7,8,9 9,6,3

I=0,j=0

TEMP=M[0][0]

M[0][0]=m[2][0]=7

M[2][0]=m[2][2]=9

M[2][2]=m[0][2]=3

M[0][2]=temp=1

I=0,j=1

TEMP=M[0][1]

M[0][1]=m[1][0]=4

M[1][0]=m[2][1]=8

M[2][1]=m[1][2]=6

m[1][2]=temp=2

reference:http://www.programcreek.com/2013/01/leetcode-rotate-image-java/

*rotate Image