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→{{header|Julia}}
Line 396:
(list, addleastreduce!(copy(list))) = ([6, 81, 243, 14, 25, 49, 123, 69, 11], [621])
</pre>
=={{header|Nim}}==
===Without sorting===
We could use the function <code>minIndex</code> from module <code>sequtils</code> but it would be less efficient. We used a single loop instead. Please note that we remove the elements using function <code>del</code> which is O(1) rather than function <code>delete</code> which is O(n).
<lang Nim># Without sorting.
import strformat
proc extractAndAddTwoSmallest(list: var seq[int]) =
var min1, min2 = int.high
var imin1, imin2 = -1
for i, val in list:
if val < min1:
min2 = min1
min1 = val
imin2 = imin1
imin1 = i
elif val < min2:
min2 = val
imin2 = i
echo &"List: {list}; two smallest: {min1}@{imin1} and {min2}@{imin2}; sum = {min1 + min2}"
if imin1 > imin2: swap imin1, imin2 # Make sure "imin2" is the greatest index.
list.del imin2
list.del imin1
list.add min1 + min2
var list = @[6, 81, 243, 14, 25, 49, 123, 69, 11]
while list.len >= 2:
list.extractAndAddTwoSmallest()
echo &"Last item is {list[0]}."</lang>
{{out}}
<pre>List: @[6, 81, 243, 14, 25, 49, 123, 69, 11]; two smallest: 6@0 and 11@8; sum = 17
List: @[69, 81, 243, 14, 25, 49, 123, 17]; two smallest: 14@3 and 17@7; sum = 31
List: @[69, 81, 243, 123, 25, 49, 31]; two smallest: 25@4 and 31@6; sum = 56
List: @[69, 81, 243, 123, 49, 56]; two smallest: 49@4 and 56@5; sum = 105
List: @[69, 81, 243, 123, 105]; two smallest: 69@0 and 81@1; sum = 150
List: @[123, 105, 243, 150]; two smallest: 105@1 and 123@0; sum = 228
List: @[243, 150, 228]; two smallest: 150@1 and 228@2; sum = 378
List: @[243, 378]; two smallest: 243@0 and 378@1; sum = 621
Last item is 621.</pre>
===With sorting===
We sort in descending order as it is more efficient.
<lang Nim># With sorting.
import algorithm, strformat
proc extractAndAddTwoSmallest(list: var seq[int]) =
list.sort(Descending)
stdout.write &"Descending sorted list: {list}"
let min1 = list.pop()
let min2 = list.pop()
echo &"; two smallest: {min1} and {min2}; sum = {min1 + min2}"
list.add min1 + min2
var list = @[6, 81, 243, 14, 25, 49, 123, 69, 11]
while list.len >= 2:
list.extractAndAddTwoSmallest()
echo &"Last item is {list[0]}."</lang>
{{out}}
<pre>Descending sorted list: @[243, 123, 81, 69, 49, 25, 14, 11, 6]; two smallest: 6 and 11; sum = 17
Descending sorted list: @[243, 123, 81, 69, 49, 25, 17, 14]; two smallest: 14 and 17; sum = 31
Descending sorted list: @[243, 123, 81, 69, 49, 31, 25]; two smallest: 25 and 31; sum = 56
Descending sorted list: @[243, 123, 81, 69, 56, 49]; two smallest: 49 and 56; sum = 105
Descending sorted list: @[243, 123, 105, 81, 69]; two smallest: 69 and 81; sum = 150
Descending sorted list: @[243, 150, 123, 105]; two smallest: 105 and 123; sum = 228
Descending sorted list: @[243, 228, 150]; two smallest: 150 and 228; sum = 378
Descending sorted list: @[378, 243]; two smallest: 243 and 378; sum = 621
Last item is 621.</pre>
=={{header|Perl}}==
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