leetcode--Spiral Matrix

Given a matrix of m x n elements (m rows, n columns), return all elements of the matrix in spiral order.

For example,
Given the following matrix:

[
 [ 1, 2, 3 ],
 [ 4, 5, 6 ],
 [ 7, 8, 9 ]
]

You should return [1,2,3,6,9,8,7,4,5].

public class Solution {
    public List<Integer> spiralOrder(int[][] matrix) {
        List<Integer> result = new ArrayList<Integer>();
		int row = matrix.length;
		if(row > 0){
			int column = matrix[0].length;
			int min = Math.min(row, column);
			for(int i = 0; i < min / 2; ++i){
				for(int k = i; k < column - i; ++k)
					result.add(matrix[i][k]);
				for(int k = (i + 1); k < row -(i + 1); ++k)
					result.add(matrix[k][column - 1 - i]);
				for(int k = i; k < column - i; ++k)
					result.add(matrix[row - 1 - i][column - 1 - k]);
				for(int k = i + 1; k < row - (i + 1); ++k)
					result.add(matrix[row - 1 - k][i]);
			}
			//exceptional cases:
			if(row % 2 != 0 && column != 1){
			    for(int k = min / 2; k < column - min / 2; ++k)
		    	    result.add(matrix[min / 2][k]);
			}
			else{
			    if(column % 2 != 0){
			        for(int k = min / 2; k < row - min / 2; ++k)
			            result.add(matrix[k][min / 2]);
			    }
			}
		}
		return result;    
    }
}

  

原文地址:https://www.cnblogs.com/averillzheng/p/3790269.html