用lua实现排序算法

冒泡排序

function bubblesort(t)
    for i=1, #t-1 do
        for j=i+1, #t do
            if (t[i]>t[j]) then 
                t[i],t[j] = t[j],t[i]
            end
        end
    end
    return t
end

arr = {3,1,7,2,9,8}
beforesort = table.concat(arr, "-")
print(beforesort)
print("---------------------------")
newarr = bubblesort(arr)
aftersort = table.concat(newarr, "-")
print(aftersort)

选择排序

重复的代码省略

function selectsort(t)
    for i=1, #t-1 do
        minindex = i
        for j=i+1, #t do  
            if t[j] < t[minindex] then
                minindex = j
            end
        end
        t[i],t[minindex] = t[minindex],t[i]
    end
    return t
end

插入排序

function insertsort(t)
    for i=1, #t-1 do
        currentvalue = t[i+1]
        insertindex = i
        while insertindex > 0 and currentvalue < t[insertindex] do
            t[insertindex+1] = t[insertindex]--将大于插入值的对象往后挪一个
            insertindex = insertindex-1
        end
        t[insertindex+1] = currentvalue
    end
    return t
end

希尔排序

function shellsort(t)   
  step = #t//2
   while step >=1 do
        for j=step+1, #t do
        temp = t[j]
            for i= j-step, 1, -step do
                if t[i] >temp then 
                    t[i+step] =t[i]
                    t[i] = temp 
                end
            end
        end
        step = step//2
    end
    return t
end

快速排序

function partition(t, left, right)
    pivot = t[left]
    while left < right do
        while left < right and t[right] >= pivot do
            right = right-1
        end
        t[left] = t[right]
        while left < right and t[left]<= pivot do
            left = left+1
        end
        t[right] = t[left]
    end
    t[left] = pivot
    return left
end

function quicksort(t, left, right)
    if (left <right) then
        local pivot  = partition(t, left, right)
        quicksort(t,left,pivot-1)
        quicksort(t,pivot+1,right)
    end
    return t
end

归并排序-待补充