Or by modifying the compound interest formula to kill off the previous generation:

use strict;
use warnings;

my $startPop = 4;
my $targetPop = 250e9;
my $increase = 2.5;
my $n = int ((log($targetPop) - log($startPop)) / log($increase) + 0.5
+);
my $pop = int ($startPop * ($increase) ** $n);

print "$pop population after $n generations\n";

[download]

Prints:

222044604925 population after 27 generations

[download]

Add 1 instead of 0.5 in the $n calculation if you want a minimum of $targetPop.

True laziness is hard work

In reply to Re^4: A script with a loop is running my computer Out of memory by GrandFather
in thread A script with a loop is running my computer Out of memory by Lady_Aleena

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