螺旋打印矩阵元素

算法：给定一个包含 m x n 个元素的矩阵（即：m行n列的矩阵），按照螺旋顺序打印出矩阵中的所有元素。

示例：给定如下矩阵
[1, 2, 3]
[4, 5, 6]
[7, 8, 9]
则最终打印出的顺序为：1, 2, 3, 6, 9, 8, 7, 4, 5

--[[
    给定一个包含 m x n 个元素的矩阵（即：m行n列的矩阵），按照螺旋顺序打印出矩阵中的所有元素。
    示例：给定如下矩阵
    [1, 2, 3]
    [4, 5, 6]
    [7, 8, 9]
    则最终打印出的顺序为：1, 2, 3, 6, 9, 8, 7, 4, 5
--]]

function traversal_print(data)
    
    local row_max     = #data;        -- max row
    local col_max     = #(data[1]);    -- max column
    
    local row         = 1;
    local col        = 1;
    local row_end    = row_max;
    local col_end    = col_max;
    
    local begin_time= os.clock();
    
    local temp         = 0;
    while (row <= row_end) and (col <= col_end) do
        for temp = col, col_end do
            print(data[row][temp]);
        end

        if row_end > row then
            for temp = row + 1, row_end do
                print(data[temp][col_end]);
            end
        end

        if (col_end > col) and (row_end > row) then
            for temp = col_end - 1, col, -1 do
                print(data[row_end][temp]);
            end
        end

        if (row_end - 1 > row) and (col_end > col) then
            for temp = row_end - 1, row + 1, -1 do
                print(data[temp][col]);
            end
        end

        if (row_end - row >= 0) and (col_end - col >= 0) then
            row     = row + 1;
            row_end = row_end - 1;
            col     = col + 1;
            col_end = col_end - 1;
        end
    end
    
    local elaplsed_time = os.clock() - begin_time;
    print("-- total elasped: "..elaplsed_time.." --"); 
end

--[[--]]
local _data        = {
                      {1, 2, 3},
                      {4, 5, 6},
                      {7, 8, 9}
                   };


--[[
local _data        = {
                      {1, 2, 3}
                   };
--]]
                   
--[[
local _data        = {
                      {1},
                      {4},
                      {7}
                   };
--]]

traversal_print(_data);

void tt5() {
    const int ROW_MAX           = 3;
    const int COL_MAX           = 3;
    int data[ROW_MAX][ROW_MAX]  = {
                                      { 1, 2, 3 },
                                      { 4, 5, 6 },
                                      { 7, 8, 9 }
                                  };
    int nRow                    = 0;
    int nCol                    = 0;
    int nRowEnd                 = ROW_MAX - 1;
    int nColEnd                 = COL_MAX - 1;
    
    const auto begin_time       = clock();
    int nTemp                   = 0;
    while (nRow <= nRowEnd && nCol <= nColEnd) {
        for (nTemp = nCol; nTemp <= nColEnd; ++nTemp) {
            std::cout << data[nRow][nTemp] << std::endl;
        }

        if (nRowEnd > nRow) {
            for (nTemp = nRow + 1; nTemp <= nRowEnd; ++nTemp) {
                std::cout << data[nTemp][nColEnd] << std::endl;
            }
        }

        if (nColEnd > nCol && nRowEnd > nRow) {
            for (nTemp = nColEnd - 1; nTemp >= nCol; --nTemp) {
                std::cout << data[nRowEnd][nTemp] << std::endl;
            }
        }

        if (nRowEnd - 1 > nRow && nColEnd > nCol) {
            for (nTemp = nRowEnd - 1; nTemp >= nRow + 1; --nTemp) {
                std::cout << data[nTemp][nCol] << std::endl;
            }
        }

        if (nRowEnd >= nRow && nColEnd >= nCol) {
            ++nRow;
            --nRowEnd;
            ++nCol;
            --nColEnd;
        }
    }
    const auto elapsed_time     = clock() - begin_time;
    std::cout << "-- total elapsed: " << elapsed_time << " --" << std::endl;
}

经多次测试，相对来说，还是c++效率会优于Lua。