fig05_04.pl

PERL语言资料 可以用于PERL程序设计

#!/usr/bin/perl
# Fig. 5.4: fig05_04.pl
# Demonstrating map and grep.

@numbers = ( 1 .. 10 );
print "\@numbers: @numbers\n\n";

# locate all numbers less than 6
foreach ( @numbers ) {
   push( @smallNumbers, $_ ) if $_ < 6;
}

print "Numbers less than 6:\n", 
      "foreach: @smallNumbers\n";

@smallNumbers2 = grep( $_ < 6, @numbers );
print "grep:    @smallNumbers2\n\n";

# multiply every number by 2
foreach ( @numbers ) {
   push( @doubledNumbers, $_ * 2 );
}

print "Double each number:\n",
      "foreach: @doubledNumbers\n";

@doubledNumbers2 = map( $_ * 2, @numbers );
print "map:     @doubledNumbers2\n";

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