Here's my tweak of vr's excellent code, for use in the perldl REPL, which doesn't feature the check, just does timing (and doesn't use strict because of the REPL), and uses "+=" instead of the wordier "->inplace->plus":

$n = 2e4;
@input = map int rand 1e5, 1 .. $n;
$sums = zeroes long, scalar @input;
$vec  = pdl long, \@input;
with_time { my @max = map +($sums( 0 : -$_ - 1 ) += $vec( $_ : -1 ))->
+maximum, 0 .. $#input };
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EDIT: in PDL 2.077 with_time is always available in the PDL shells so I removed the definition of it here.