小骆驼 第五章 输入与输出

输出到标准输出

ssssssssssss
ssssssssss
dddddddddddd
2222222222
sssssssssssssssss

#!/usr/bin/perl

use strict;
use warnings;

my @arr = (1,2,3,3);
print "@arr\n";
print @arr."\n";
print @arr;
print "\n";

##1 2 3 3
##4
##1233

my @arr_1 = 
qw{
     1
     2
     3
  };
print "@arr_1\n";
print @arr_1;

##1 2 3
##123

cat 3.txt| perl test.pl

print <>;

my $print = print(3+6);print "\n";print "$print\n";

##9
##9
##1

print (3+6)*2;print "\n";

my $print_add = print (3+6)*2;print "\n";print "$print_add\n";

##9
##9
##2

print ((3+6)*2);print "\n";

##18

printf "%g\n",56*2.3;

printf "%3d\n",0.9077777;

printf "%3f\n",0.9077777;

printf "%3.3f\n",0.9077777;

printf "%-5s\n",'app';

printf "%5s\n",'app';

#128.8
#  0
#0.907778
#0.908
#app
#  app

printf "%3d%%\n",3.6;

#3%

my @number = ('a','b','c','d','e');printf "". ("%6s\n" x @number),@number;

#     a
#     b
#     c
#     d
#     e
#

my @items = qw(a b c);printf "I saw\n". ("%10s\n" x @items),@items;

#I saw
#         a
#         b
#         c
#