CareerCup_1.6@1point3acres

6.cpp

/*
	Q: Given an image represented by an NxN matrix,
	 where each pixel in the image is 4 bytes, write 
	 a method to rotate the image by 90 degrees
	 Can you do this in place?
	 
*/

/*
	C++传递二维数组比较麻烦
*/

#include <iostream>
using namespace std;

void rotate(int matrix[][4], int n)
{
	for(int i = 0; i < n/2; i++)
	{
		for(int j = 0; j < n/2; j++)
		{
			int temp = matrix[i][j];
			matrix[i][j] = matrix[j][n - i - 1];
			matrix[j][n - i - 1] = matrix[n - i - 1][n - j - 1];
			matrix[n - i - 1][n - j - 1] = matrix[n - j - 1][i];
			matrix[n - j - 1][i] = temp;
		}
	}
}

int main()
{
	int matrix[4][4] = {1, 2, 3, 4,
						5, 6, 7, 8,
						9, 10, 11, 12,
						13, 14, 15, 16
						};
	rotate(matrix, 4);
	for(int i = 0; i < 4; i++)
	{
		for(int j = 0; j < 4; j++)
			cout << matrix[i][j] << " ";
		cout << endl;
	}
	return 0;
}