The solution of the Unnamed One is correct but a little terse if you are still learning. Here's a more spelled-out version of the same general idea: 
#!/usr/bin/perl -w
use strict;

my %hash;
# Do it
for (<DATA>) {
   my ($name, $score, $date) = split /\|/;
   $hash{$name}++;
}
#Show it
for (keys %hash) {
   print "$_ = $hash{$_}\n";
}
__DATA__
name_x|score|date
name_y|score|date
name_z|score|date
name_x|score|date
name_z|score|date
name_z|score|date

[download]
And just to explain what is happening with AM's solution: $name{(split/\|/)[0]} += 1; (split/\|/) returns a list which is then subscripted to get the zeroth element which is then used as the key for the %name hash. The value associated with that key (which may be magically created if it didn't exist before) is increased by one using the += assignment operator.

Just a word of encouragement about hashes. They are a wonderful tool for many purposes. And it is commonly said that you are not really programming in Perl until you can think in terms of hashes. Your point about their lacking a fixed order is well taken, but once you begin using hashes, you may be pleasantly surprised to discover how often that doesn't matter.

In reply to Re: Counting incidents of names in a file by dvergin
in thread Counting incidents of names in a file by Bishma

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