Go 代码

func printMatrix(matrix [][]int) []int {
    if len(matrix) == 0 {
        return nil
    }
    r, c := len(matrix), len(matrix[0])
    var res []int
    for i, j := 0, 0; i <= (r-1)>>1 && j <= (c-1)>>1; i, j = i+1, j+1 {
        res = append(res, matrix[i][j:c-j]...)
        for k := i+1; k < r-i-1; k++ {
            res = append(res, matrix[k][c-j-1])
        }
        if r-i-1 != i {
            for k := c-j-1; k >= j; k-- {
                res = append(res, matrix[r-i-1][k])
            }
        }
        if c-j-1 != j {
            for k := r-i-2; k >= i+1; k-- {
                res = append(res, matrix[k][j])
            }
        }
    }
    return res
}