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→{{header|ALGOL 68}}: Re-added sorted version, with the correct positioning of the new element (was wrong due to an error in translation)
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=={{header|ALGOL 68}}==
===With sorting===
{{trans|Wren}}
<lang algol68>
BEGIN # find the last element after repeatedely adding the sum #
# of the two smallest elements and removing them #
# Quicksorts in-place the array of integers a, from lb to ub #
PROC quicksort = ( REF[]INT a, INT lb, ub )VOID:
IF ub > lb THEN
# more than one element, so must sort #
INT left := lb;
INT right := ub;
# choosing the middle element of the array as the pivot #
INT pivot := a[ left + ( ( right + 1 ) - left ) OVER 2 ];
WHILE
WHILE IF left <= ub THEN a[ left ] < pivot ELSE FALSE FI DO left +:= 1 OD;
WHILE IF right >= lb THEN a[ right ] > pivot ELSE FALSE FI DO right -:= 1 OD;
left <= right
DO
INT t := a[ left ];
a[ left ] := a[ right ];
a[ right ] := t;
left +:= 1;
right -:= 1
OD;
quicksort( a, lb, right );
quicksort( a, left, ub )
FI # quicksort # ;
[ 1 : 9 ]INT a := ( 6, 81, 243, 14, 25, 49, 123, 69, 11 );
INT a count := UPB a;
WHILE a count > 1 DO
quicksort( a, LWB a, a count );
print( ( "Sorted list:" ) );FOR i TO a count DO print( ( " ", whole( a[ i ], 0 ) ) ) OD;
INT sum = a[ 1 ] + a[ 2 ];
print( ( "; two smallest: " , whole( a[ 1 ], 0 )
, " + ", whole( a[ 2 ], 0 )
, " = ", whole( sum, 0 )
, newline
)
);
a[ 1 : a count - 2 ] := a[ 3 : a count ];
a count -:= 1 ;
a[ a count ] := sum
OD;
print( ( "Last item is ", whole( a[ 1 ], 0 ), ".", newline ) )
END
</lang>
{{out}}
<pre>
Sorted list: 6 11 14 25 49 69 81 123 243; two smallest: 6 + 11 = 17
Sorted list: 14 17 25 49 69 81 123 243; two smallest: 14 + 17 = 31
Sorted list: 25 31 49 69 81 123 243; two smallest: 25 + 31 = 56
Sorted list: 49 56 69 81 123 243; two smallest: 49 + 56 = 105
Sorted list: 69 81 105 123 243; two smallest: 69 + 81 = 150
Sorted list: 105 123 150 243; two smallest: 105 + 123 = 228
Sorted list: 150 228 243; two smallest: 150 + 228 = 378
Sorted list: 243 378; two smallest: 243 + 378 = 621
Last item is 621.
</pre>
===Without sorting===
Was a translation of the sorted Wren version but the sorting has been removed as per the revised task requirements.
<lang algol68>BEGIN # find the last element after repeatedly adding the sum #
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