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September 2017 Update

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Ingy döt Net 2017-09-23 10:01:46 +02:00
parent bba7bfd280
commit ba8067c3b7
14570 changed files with 153136 additions and 63871 deletions
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8
Task/Modular-exponentiation/REXX/modular-exponentiation-1.rexx
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@ -18,9 +18,9 @@ powerMod: procedure; parse arg x,p,n /*fast modular exponentiat
if p<0 then do; say '***error*** power is negative:' p; exit 13; end
parse value max(x**2,p,n)'E0' with "E" e /*obtain the biggest of the three.*/
numeric digits max(20, e*2) /*big enough to handle A². */
_=1 /*use this for the first value. */
$=1 /*use this for the first value. */
do while p\==0 /*perform while P isn't zero.*/
if p//2 then _=_*x//n /*is P odd? (is ÷ remainder≡1).*/
p=p%2; x=x*x//n /*halve P; calculate x² mod n */
if p//2 then $=$ * x // n /*is P odd? (is ÷ remainder≡1).*/
p=p%2; x=x * x // n /*halve P; calculate x² mod n */
end /*while*/ /* [↑] keep mod'ing 'til equal 0.*/
return _
return $