Re^3: for-loop issue - swap gets crazy large

[ikegami]

my @last_distance;  # Use instead of @{ $distance[$u-1] }
my @this_distance;  # Use instead of @{ $distance[$u-0] }
for($u = 0;  $u < $U;  $u++ ) {   
  ...
  @last_distance = @this_distance;
}