Let me suggest Perl, as this site is mostly about Perl.

I would assume most of the syntax you would use is found in your course material, but also in perlsyn. Personally, I would look at perlrun and use the "autosplit" parameter, together with push and print, and the if statement.

A perly way using a regex code evaluation expression.

while (<DATA>){
    m/
        (\w+)\s(\d+)\s(\d+)\s(\w+)
        (?{$_ = "$1 $3 $2 $4 +" if $2 > $3})
    /x;
    ...
}
[download]

for(@input){
    if($_[1] gt $_[2]){
    push (@output, "$_[0] $_[2] $_[1] $[3] +");
}

print "$_\n" for @output;
[download]

use strict;
use warnings;

my @input;
my @output;

while (<DATA>) {
    push @input, $_;
}
for (@input) {
    my @temp = split( /\s+/, $_ ); # you split on a delimiter, which i
+s 1 or more spaces in this case

    if ( $temp[1] gt $temp[2] ) {
        push( @output, "$temp[0] $temp[2] $temp[1] $temp[3] +" );
    }
    else {
        push @output, "$temp[0] $temp[1] $temp[2] $temp[3]";
    }
}

print "$_\n" for @output

__DATA__
red 15 2 smith
blue 4 10 walter
[download]

This would be a very silly way to accomplish this, but it works. :)

use strict;
use warnings;
use Data::Dumper;
use Spreadsheet::Engine;

my @data = (
    [qw( red 15 2 smith )],
    [qw( blue 4 10 walter )],
    [qw( blue 4 10 walter )],
    [qw( red 15 2 smith )],
);

my @commands = (
    'set E_ formula IF(B_>C_,B_,"")',
    'set F_ formula IF(B_<C_,B_,"")',
    'set B_ formula IF(E_,C_,F_)',
    'set F_ formula IF(B_<C_,C_,"")',
    'set C_ formula IF(E_,E_,F_)',
    'set E_ formula IF(F_,"","+")',
    'set F_ value v',
);

my $sheet = import( @data );

for my $row (0 .. $#data) {
    $sheet = apply( $sheet, $_, $row + 1 ) for @commands;
}

print Dumper [ export( $sheet ) ];

sub apply {
    my ($sheet, $formula, $row) = @_;
    $formula =~ s/_/$row/g;
    $sheet->execute( $formula );
    $sheet->recalc;
    import( export( $sheet ) );
}

sub import {
    my @data = @_;
    my $sheet = Spreadsheet::Engine->new;
    for my $row (0 .. $#data)  {
        for my $col (0 .. $#{ $data[$row] }) {
            my $key = Spreadsheet::Engine::Sheet::number_to_col( $col 
++ 1 ) . ( $row + 1 );
            my $val = $data[$row][$col] || '';
            my $type = $val =~ /\D/ ? 'v' : 'n';
            $sheet->execute( "set $key value $type $val" );
        }
    }
    return $sheet;
}

sub export {
    my $sheet = shift;
    my @data  = ();
    for my $row (0 .. $sheet->raw->{sheetattribs}{lastrow} - 1) {
        my @tmp;
        for my $col (0 .. $sheet->raw->{sheetattribs}{lastcol} - 1) {
            my $key = Spreadsheet::Engine::Sheet::number_to_col( $col 
++ 1 ) . ( $row + 1 );
            push @tmp, $sheet->raw->{datavalues}{$key};
        }
        push @data, [@tmp];
        @tmp = ();
    }
    return @data;
}


__DATA__
$VAR1 = [
          [
            'red',
            '2',
            '15',
            'smith',
            '+',
            ''
          ],
          [
            'blue',
            '4',
            '10',
            'walter',
            '',
            ''
          ],
          [
            'blue',
            '4',
            '10',
            'walter',
            '',
            ''
          ],
          [
            'red',
            '2',
            '15',
            'smith',
            '+',
            ''
          ]
        ];
[download]

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)