#!/usr/bin/perl use strict; use warnings; use list::util 'max';  # function to count groups of three or more repeating characters sub count_repeats {     my ($str) = @_;     my $repeats = 0;      # find repeating characters and count the required changes     while ($str =~ /(.)1{2,}/g) {         $repeats += int(length($&amp;) / 3);     }      return $repeats; }  # function to calculate the minimum steps to create a strong password sub minimum_steps_to_strong_password {     my ($str) = @_;     my $length = length($str);      # check if the password contains the required character types     my $has_lower = $str =~ /[a-z]/;     my $has_upper = $str =~ /[a-z]/;     my $has_digit = $str =~ /d/;      # calculate the number of types needed     my $types_needed = !$has_lower + !$has_upper + !$has_digit;     my $repeats = count_repeats($str);      # return the minimum steps based on the length of the password     return ($length     <h4>         perl 实现的测试 </h4>    <pre class="brush:php;toolbar:false">use strict; use warnings; use test::more; require "./ch-1.pl";  my @tests = (     ["a", 5],     ["ab2", 3],     ["paasw0rd", 0],     ["paaasw0rd", 1],     ["aaaaa", 2], );  foreach my $test (@tests) {     my ($input, $expected) = @$test;     my $result = minimum_steps_to_strong_password($input);     is($result, $expected, "input: '$input'"); }  done_testing(); 

package main  import (     "regexp" )  func countrepeats(password string) int {     repeats := 0     count := 1      for i := 1; i  b {         return a     }     return b } 

package main  import (     "testing" )  func testminimumstepstostrongpassword(t *testing.t) {     tests := []struct {         password string         expected int     }{         {"a", 5},         {"ab2", 3},         {"paasw0rd", 0},         {"paaasw0rd", 1},         {"aaaaa", 2},     }      for _, test := range tests {         result := minimumstepstostrongpassword(test.password)         if result != test.expected {             t.errorf("for password '%s', expected %d but got %d", test.password, test.expected, result)         }     } } 

#!/usr/bin/perl use strict; use warnings;  sub is_valid_number {     my ($str) = @_;      # regex for valid numbers     my $regex = qr{         ^            # start of the string         [+-]?        # optional sign         (?:          # start of the number group             d+      # integer: at least one digit             (?:      # start of the optional decimal part                 .   # decimal point                 d*  # followed by zero or more digits             )?       # group is optional             |        # or             .       # just a decimal point             d+      # followed by one or more digits         )            # end of the number group         (?:          # start of the optional exponent group             [ee]     # 'e' or 'e'             [+-]?    # optional sign             d+      # followed by one or more digits         )?           # exponent is optional         $            # end of the string     }x;      # return 1 for valid, 0 for invalid     return $str =~ $regex ? 1 : 0; }  1; 

#!/usr/bin/perl use strict; use warnings; use test::more;  require './ch-2.pl';  # define test cases my @test_cases = (     ["1", 1, 'valid integer'],     ["a", 0, 'invalid input'],     [".", 0, 'single dot'],     ["1.2e4.2", 0, 'invalid exponent'],     ["-1.", 1, 'valid decimal'],     ["+1e-8", 1, 'valid scientific notation'],     [".44", 1, 'valid decimal starting with dot'], );  # loop through test cases and run tests foreach my $case (@test_cases) {     my $result = is_valid_number($case->[0]);     is($result, $case->[1], $case->[2]); }  done_testing(); 

package main  import (     "regexp" )  // isvalidnumber checks if the given string is a valid number. func isvalidnumber(str string) bool {     regex := `^[+-]?((d+(.d*)?)|(.d+))([ee][+-]?d+)?$`     matched, _ := regexp.matchstring(regex, str)     return matched } 

package main  import (     "testing" )  func TestIsValidNumber(t *testing.T) {     testCases := []struct {         input    string         expected bool     }{         {"1", true},         {"a", false},         {".", false},         {"1.2e4.2", false},         {"-1.", true},         {"+1E-8", true},         {".44", true},     }      for _, tc := range testCases {         result := isValidNumber(tc.input)         if result != tc.expected {             t.Errorf("isValidNumber(%q) = %v; expected %v", tc.input, result, tc.expected)         }     } }