Recursion AWK失败的递归调用？
我正在尝试实现中定义的快速排序的简单变体。然而，在我看来，旧的递归调用中的局部变量正在泄漏到后面的调用中。（我目前的解释）。是这样吗？有解决办法吗 下面是示例代码Recursion AWK失败的递归调用？,recursion,scope,awk,quicksort,Recursion,Scope,Awk,Quicksort,我正在尝试实现中定义的快速排序的简单变体。然而，在我看来，旧的递归调用中的局部变量正在泄漏到后面的调用中。（我目前的解释）。是这样吗？有解决办法吗 下面是示例代码 # Quick sort - Simple variant. Requires 0(n) extra store # Divide and conquer. Pick a pivot, compare elements to # pivot generating two sublists; one greater than pivo
# Quick sort - Simple variant. Requires 0(n) extra store
# Divide and conquer. Pick a pivot, compare elements to
# pivot generating two sublists; one greater than pivot
# and the other less than pivot. Sort these two recursively.
# See http://en.wikipedia.org/wiki/Quicksort#Simple_version
function dump_array(arr_arg){
arr_arg_len = length(arr_arg)
RSEP = ORS;
ORS=" ";
dctr = 1;
# Do not use length(arr_arg) in place of arr_arg
# It fails. The following doesn't work
#while (dctr <= arr_arg_len){
while (dctr <= arr_arg_len){
print arr_arg[dctr];
dctr++;
};
ORS = RSEP;
print "\n";
}
function simple_quicksort(unsorted_str)
{
# Unpack from the str - space separated
print "******************************"
print "Called with "unsorted_str
# Split the space separated string into an array
split(unsorted_str, unsorted_array, " ");
array_len = length(unsorted_array);
# No more sorting to be done. Break recursion
if (array_len <= 1){
print "Ending recursion with "unsorted_str
return unsorted_str
}
# Pick a random value as pivot
# index must not be 0
idx = 0
while (idx == 0){
srand()
idx = int(rand() * array_len)
}
pivot = unsorted_array[idx]
if (debug >= 1){
print "idx:"idx" pivot is: "pivot
}
num = 1;
# we don't use the zero'th element,
# this helps us declare an empty array
# dunno any other method
# we'll remove it anyway
less_arr[0] = 0
less_ctr = 1
more_arr[0] = 0
more_ctr = 1
while (num <= array_len){
# Skip pivot
if (idx != num){
if (unsorted_array[num] <= pivot){
if (debug >= 1){
print "Element less than pivot: "unsorted_array[num]
}
less_arr[less_ctr] = unsorted_array[num]
less_ctr++;
}else{
if (debug >= 1){
print "Element more than pivot: "unsorted_array[num]
}
more_arr[more_ctr] = unsorted_array[num]
more_ctr++;
}
}
num++
};
# strip out the holder in idx 0
delete less_arr[0]
delete more_arr[0]
if (debug >= 1){
print "Less than pivot:"
print dump_array(less_arr)
print "More than pivot:"
print dump_array(more_arr)
}
# Marshal array back to a string
less_str=""
less_length = length(less_arr)
num = 1
print "Less length: "less_length
while (num <= less_length){
less_str = less_str" "less_arr[num]
num++;
}
# same thing for more
more_str=""
more_length = length(more_arr)
num = 1
while (num <= more_length){
more_str = more_str" "more_arr[num]
num++;
}
if (debug >= 1){
print "Going for a recursive call with elements < pivot: "less_str
print "Going for a recursive call with elements > pivot: "more_str
print "pivot was: "pivot
}
# Tried to delete the local variables
# Coz it seems like local vars are visible to recursed functions
# Is this why it fails?
delete less_arr
delete more_arr
delete unsorted_array
print "^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^"
print ""
return simple_quicksort(less_str) " "pivot" "simple_quicksort(more_str)
}
BEGIN{
print "-- quick sort --"
}
{
# print the unsorted objects
print "Unsorted "NF" objects:\n"$0;
# We'll use a slightly different method,
# Pass the $0 string to the sorter, let it split
# it into an array, qsort that array, generate sub-
# strings and recursively qsort them
#Simple version
sorted = simple_quicksort($0)
}
END{
print "Sorted "NF" objects";
print "Sorted >>"sorted
}
#快速排序-简单变体。需要0（n）个额外存储
#分而治之。选择一个轴，将图元与
#枢轴生成两个子列表；比枢轴大一个
#另一个比枢轴小。对这两个进行递归排序。
#看http://en.wikipedia.org/wiki/Quicksort#Simple_version
函数转储数组（arr\u arg）{
arr_arg_len=长度（arr_arg）
RSEP=ORS；
ORS=“”；
dctr=1；
#不要用长度（arr_arg）代替arr_arg
#它失败了。以下操作不起作用
#而（dctr枢轴：12 7 13719 28019 21444 30578 30647
数据为：5
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
******************************
电话号码是2
以2结束递归
******************************
致电12 7 13719 28019 21444 30578 30647
idx:1轴是：12
元素小于枢轴：7
元素多于枢轴：13719
元素多于枢轴：28019
元素多于枢轴：21444
元素多于枢轴：30578
元素多于枢轴：30647
小于枢轴：
7.
不仅仅是支点：
13719 28019 21444 30578 30647
小于长度：1
使用元素pivot进行递归调用：13719 28019 21444 30578 30647
数据为：12
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
******************************
7点打电话
以7结束递归
******************************
致电13719 28019 21444 30578 30647
idx:3枢轴为：21444
元素小于枢轴：13719
元素多于枢轴：28019
元素多于枢轴：30578
元素多于枢轴：30647
小于枢轴：
13719
不仅仅是支点：
28019 30578 30647
小于长度：1
使用元素进行递归调用pivot进行递归调用：28019 30578 30647
数据为：21444
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
******************************
电话是13719
以13719结束递归
******************************
致电28019 30578 30647
idx:1枢轴为：28019
元素多于枢轴：30578
元素多于枢轴：30647
小于枢轴：
不仅仅是支点：
30578 30647
小于长度：0
使用元素pivot进行递归调用：30578 30647
数据为：28019
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
******************************
打电话给
以结束递归
******************************
致电3057830647
idx:1枢轴为：30578
元素多于枢轴：30647
小于枢轴：
不仅仅是支点：
30647
小于长度：0
使用元素pivot:30647进行递归调用
数据来源：30578
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
******************************
打电话给
以结束递归
******************************
电话是30647
以30647结束递归
已排序的9个对象
已排序>>2 5 7 12 13719 21444 28019 30578 30647
$ echo 5 12 7 2 13719 28019 21444 30578 30647 | awk -f devel/andorian-blog/awk/sorting/quick_sort.awk -v debug=1
-- quick sort --
Unsorted 9 objects:
5 12 7 2 13719 28019 21444 30578 30647
******************************
Called with 5 12 7 2 13719 28019 21444 30578 30647
idx:6 pivot is: 28019
Element less than pivot: 5
Element less than pivot: 12
Element less than pivot: 7
Element less than pivot: 2
Element less than pivot: 13719
Element less than pivot: 21444
Element more than pivot: 30578
Element more than pivot: 30647
Less than pivot:
5 12 7 2 13719 21444
More than pivot:
30578 30647
Less length: 6
Going for a recursive call with elements < pivot: 5 12 7 2 13719 21444
Going for a recursive call with elements > pivot: 30578 30647
pivot was: 28019
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
******************************
Called with 5 12 7 2 13719 21444
idx:4 pivot is: 2
Element more than pivot: 5
Element more than pivot: 12
Element more than pivot: 7
Element more than pivot: 13719
Element more than pivot: 21444
Less than pivot:
More than pivot:
5 12 7 13719 21444
Less length: 0
Going for a recursive call with elements < pivot:
Going for a recursive call with elements > pivot: 5 12 7 13719 21444
pivot was: 2
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
******************************
Called with
Ending recursion with
******************************
Called with 5 12 7 13719 21444
idx:3 pivot is: 7
Element less than pivot: 5
Element more than pivot: 12
Element more than pivot: 13719
E lement more than pivot: 21444
Less than pivot:
5
More than pivot:
12 13719 21444
Less length: 1
Going for a recursive call with elements < pivot: 5
Going for a recursive call with elements > pivot: 12 13719 21444
pivot was: 7
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
******************************
Called with 5
Ending recursion with 5
******************************
Called with 12 13719 21444
idx:2 pivot is: 13719
Element less than pivot: 12
Element more than pivot: 21444
Less than pivot:
1 2
More than pivot:
21444
Less length: 1
Going for a recursive call with elements < pivot: 12
Going for a recursive call with elements > pivot: 21444
pivot was: 13719
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
******************************
Called with 12
Ending recursion with 12
******************************
Called with 21444
Ending recursion with 21444
******************************
Called with 21444
Ending recursion with 21444
Sorted 9 objects
Sorted >> 2 5 7 12 13719 21444 13719 21444
$echo 5 12 7 2 13719 28019 21444 30578 30647 | awk-f devel/androian blog/awk/sorting/quick_sort.awk-v debug=1
--快速排序--
未排序的9个对象：
5 12 7 2 13719 28019 21444 30578 30647
******************************
致电512721371928019214443057830647
idx:6枢轴is:28019
元素小于枢轴：5
小于枢轴的元素：12
元素小于枢轴：7
元素小于枢轴：2
元素小于枢轴：13719
元素小于枢轴：21444
元素多于枢轴：30578
元素多于枢轴：30647
小于枢轴：
5 12 7 2 13719 21444
不仅仅是支点：
30578 30647
小于长度：6
使用元素进行递归调用pivot进行递归调用：30578 30647
数据为：28019
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
******************************
致电512721371921444
idx:4枢轴为：2
元素多于枢轴：5
元素多于枢轴：12
元素多于枢轴：7
元素多于枢轴：13719
元素多于枢轴：21444
小于枢轴：
不仅仅是支点：
5 12 7 13719 21444
小于长度：0
使用元素pivot进行递归调用：5 12 7 13719 21444
数据为：2
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
******************************
打电话给
以结束递归
******************************
致电51271371921444
idx:3轴是：7
元素小于枢轴：5
元素多于枢轴：12
元素多于枢轴：13719
E超过枢轴：21444
小于枢轴：
5.
不仅仅是支点：
12 13719 21444
小于长度：1
使用元素pivot进行递归调用：12 13719 21444
数据为：7
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
******************************
打电话给5
以5结束递归
******************************
电话：121371921444
idx:2枢轴为：13719
小于枢轴的元素：12
元素多于枢轴：21444
小于枢轴：
1 2
不仅仅是支点：
21444
小于长度：1
使用元素pivot:21444进行递归调用
数据来源：13719
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
******************************
12人打电话
以12结束递归
******************************
电话是21444
以21444结束递归
******************************
电话是21444
以21444结束递归
已排序的9个对象
已排序>>2 5 7 12 13719 21444 13719 21444
$ echo 5 12 7 2 13719 28019 21444 30578 30647 | awk -f devel/andorian-blog/awk/sorting/quick_sort.awk -v debug=1
-- quick sort --
Unsorted 9 objects:
5 12 7 2 13719 28019 21444 30578 30647
******************************
Called with 5 12 7 2 13719 28019 21444 30578 30647
idx:6 pivot is: 28019
Element less than pivot: 5
Element less than pivot: 12
Element less than pivot: 7
Element less than pivot: 2
Element less than pivot: 13719
Element less than pivot: 21444
Element more than pivot: 30578
Element more than pivot: 30647
Less than pivot:
5 12 7 2 13719 21444
More than pivot:
30578 30647
Less length: 6
Going for a recursive call with elements < pivot: 5 12 7 2 13719 21444
Going for a recursive call with elements > pivot: 30578 30647
pivot was: 28019
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
******************************
Called with 5 12 7 2 13719 21444
idx:4 pivot is: 2
Element more than pivot: 5
Element more than pivot: 12
Element more than pivot: 7
Element more than pivot: 13719
Element more than pivot: 21444
Less than pivot:
More than pivot:
5 12 7 13719 21444
Less length: 0
Going for a recursive call with elements < pivot:
Going for a recursive call with elements > pivot: 5 12 7 13719 21444
pivot was: 2
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
******************************
Called with
Ending recursion with
******************************
Called with 5 12 7 13719 21444
idx:3 pivot is: 7
Element less than pivot: 5
Element more than pivot: 12
Element more than pivot: 13719
E lement more than pivot: 21444
Less than pivot:
5
More than pivot:
12 13719 21444
Less length: 1
Going for a recursive call with elements < pivot: 5
Going for a recursive call with elements > pivot: 12 13719 21444
pivot was: 7
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
******************************
Called with 5
Ending recursion with 5
******************************
Called with 12 13719 21444
idx:2 pivot is: 13719
Element less than pivot: 12
Element more than pivot: 21444
Less than pivot:
1 2
More than pivot:
21444
Less length: 1
Going for a recursive call with elements < pivot: 12
Going for a recursive call with elements > pivot: 21444
pivot was: 13719
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
******************************
Called with 12
Ending recursion with 12
******************************
Called with 21444
Ending recursion with 21444
******************************
Called with 21444
Ending recursion with 21444
Sorted 9 objects
Sorted >> 2 5 7 12 13719 21444 13719 21444