Question

perl中如何将按hash的排序方法

Answer 1

如果是按ASCII码排序，则代码如下：

foreach my $key ( sort { $hash{$a} cmp $hash{$b} } keys %hash ) {
my $value = $hash{$key};
# do something with ($key, $value)
}

如果是按数字小到大排列，则代码如下：

foreach my $key ( sort { $hash{$a} <=> $hash{$b} } keys %hash ) {
my $value = $hash{$key};
#do something with ($key, $value)
}

如果是按数字大到小排列，则代码如下：

foreach my $key ( sort { $hash{$b} <=> $hash{$a} } keys %hash ) {
my $value = $hash{$key};
#do something with ($key, $value)
}

按KEY排列

foreach my $item (sort {$a<=>$b} keys %hash){
print "$item  == > $hash{$item}","/n";
}