Distinct palindromes within decimal numbers: Difference between revisions
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1320267947849490361205695 false |
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</pre> |
</pre> |
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=={{header|Raku}}== |
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A minor modification of the [[Longest_palindromic_substrings#Raku|Longest palindromic substrings]] task. As such, works for any string, not just integers. |
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<lang perl6>use Sort::Naturally; |
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sub getpal ($str) { |
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my @chars = $str.comb; |
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my @pal = flat @chars, |
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(1 ..^ @chars).map: -> \idx { |
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my @s; |
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for 1, 2 { |
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my int ($rev, $fwd) = $_, 1; |
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loop { |
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quietly last if ($rev > idx) || (@chars[idx - $rev] ne @chars[idx + $fwd]); |
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$rev = $rev + 1; |
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$fwd = $fwd + 1; |
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} |
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@s.push: @chars[idx - $rev ^..^ idx + $fwd].join if $rev + $fwd > 2; |
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last if @chars[idx - 1] ne @chars[idx]; |
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} |
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next unless +@s; |
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@s |
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} |
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@pal.unique.sort({.chars, &naturally}); |
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} |
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say 'All palindromic substrings including (bizarrely enough) single characters:'; |
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put "$_ => ", getpal $_ for 100..125; |
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put "\nDo these strings contain a minimum two character palindrome?"; |
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printf "%25s => %s\n", $_, getpal($_).tail.chars > 1 for flat |
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9, 169, 12769, 1238769, 123498769, 12346098769, 1234572098769, |
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123456832098769, 12345679432098769, 1234567905432098769, |
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123456790165432098769, 83071934127905179083, 1320267947849490361205695, |
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<Do these strings contain a minimum two character palindrome?></lang> |
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{{out}} |
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<pre>All palindromic substrings including (bizarrely enough) single characters: |
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100 => 1 0 00 |
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101 => 1 0 101 |
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102 => 1 0 2 |
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103 => 1 0 3 |
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104 => 1 0 4 |
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105 => 1 0 5 |
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106 => 1 0 6 |
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107 => 1 0 7 |
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108 => 1 0 8 |
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109 => 1 0 9 |
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110 => 1 0 11 |
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111 => 1 11 111 |
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112 => 1 2 11 |
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113 => 1 3 11 |
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114 => 1 4 11 |
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115 => 1 5 11 |
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116 => 1 6 11 |
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117 => 1 7 11 |
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118 => 1 8 11 |
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119 => 1 9 11 |
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120 => 1 2 0 |
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121 => 1 2 121 |
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122 => 1 2 22 |
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123 => 1 2 3 |
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124 => 1 2 4 |
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125 => 1 2 5 |
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Do these strings contain a minimum two character palindrome? |
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9 => False |
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169 => False |
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12769 => False |
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1238769 => False |
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123498769 => False |
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12346098769 => False |
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1234572098769 => False |
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123456832098769 => False |
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12345679432098769 => False |
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1234567905432098769 => False |
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123456790165432098769 => False |
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83071934127905179083 => False |
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1320267947849490361205695 => True |
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Do => False |
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these => True |
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strings => False |
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contain => False |
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a => False |
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minimum => True |
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two => False |
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character => True |
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palindrome? => False</pre> |
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=={{header|Wren}}== |
=={{header|Wren}}== |
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Revision as of 20:41, 6 April 2021
Distinct palindromes within decimal numbers is a draft programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.
Find all distinct palindromes contained as substrings in decimal representation of n. Note that for the purpose of the initial function, a single digit will be considered a palindrome.
- Task
- Find all the palindromes including single digits in the integers from 100 to 125, inclusive.
- Determine which if any of the following decimal integers contain palindromes of 2 digits or more:
9, 169, 12769, 1238769, 123498769, 12346098769, 1234572098769, 123456832098769, 12345679432098769, 1234567905432098769, 123456790165432098769, 83071934127905179083, 1320267947849490361205695
- Also see
-
- OEIS entry: A262188 (Task 1).
- OEIS entry: A151997 (Task 2).
Related tasks
Palindrome_detection
Longest_palindromic_substrings
N_1's_followed_by_a_3
Factor
<lang factor>USING: formatting io kernel math math.ranges present prettyprint sequences sequences.extras sets ;
- dpal ( n -- seq )
present all-subseqs members [ dup reverse = ] filter ;
! task 1 "Number Palindromes" print 100 125 [a..b] [ dup pprint bl bl bl bl bl dpal . ] each nl
! task 2 "Number Has no >= 2 digit-palindromes?" print { 9 169 12769 1238769 123498769 12346098769 1234572098769
123456832098769 12345679432098769 1234567905432098769 123456790165432098769 83071934127905179083 1320267947849490361205695 }
[ dup dpal [ length 2 < ] reject empty? "%-25d %u\n" printf ] each</lang>
- Output:
Number Palindromes
100 { "1" "0" "00" }
101 { "1" "0" "101" }
102 { "1" "0" "2" }
103 { "1" "0" "3" }
104 { "1" "0" "4" }
105 { "1" "0" "5" }
106 { "1" "0" "6" }
107 { "1" "0" "7" }
108 { "1" "0" "8" }
109 { "1" "0" "9" }
110 { "1" "0" "11" }
111 { "1" "11" "111" }
112 { "1" "2" "11" }
113 { "1" "3" "11" }
114 { "1" "4" "11" }
115 { "1" "5" "11" }
116 { "1" "6" "11" }
117 { "1" "7" "11" }
118 { "1" "8" "11" }
119 { "1" "9" "11" }
120 { "1" "2" "0" }
121 { "1" "2" "121" }
122 { "1" "2" "22" }
123 { "1" "2" "3" }
124 { "1" "2" "4" }
125 { "1" "2" "5" }
Number Has no >= 2 digit-palindromes?
9 t
169 t
12769 t
1238769 t
123498769 t
12346098769 t
1234572098769 t
123456832098769 t
12345679432098769 t
1234567905432098769 t
123456790165432098769 t
83071934127905179083 t
1320267947849490361205695 f
Julia
<lang julia>function allpalindromes(a::Vector{T}) where T
pals = Vector{Vector{T}}([[x] for x in a])
len = length(a)
len < 2 && return pals
a == reverse(a) && push!(pals, a)
len == 2 && return pals
for i in 2:len
left = a[1:i]
left == reverse(left) && push!(pals, left)
end
return unique(vcat(pals, allpalindromes(a[2:end])))
end
println("Number Palindromes") for n in 100:125
println(" ", rpad(n, 7), sort(allpalindromes(digits(n))))
end
palindrome2plusfree(n) = (a = allpalindromes(digits(n)); all(x -> length(x) == 1, a))
println("\nNumber Has no >= 2 digit palindromes") for n in [9, 169, 12769, 1238769, 123498769, 12346098769, 1234572098769, 123456832098769,
12345679432098769, 1234567905432098769, 123456790165432098769, 83071934127905179083, 1320267947849490361205695] println(rpad(n, 26), palindrome2plusfree(n))
end
</lang>
- Output:
Number Palindromes 100 [[0], [0, 0], [1]] 101 [[0], [1], [1, 0, 1]] 102 [[0], [1], [2]] 103 [[0], [1], [3]] 104 [[0], [1], [4]] 105 [[0], [1], [5]] 106 [[0], [1], [6]] 107 [[0], [1], [7]] 108 [[0], [1], [8]] 109 [[0], [1], [9]] 110 [[0], [1], [1, 1]] 111 [[1], [1, 1], [1, 1, 1]] 112 [[1], [1, 1], [2]] 113 [[1], [1, 1], [3]] 114 [[1], [1, 1], [4]] 115 [[1], [1, 1], [5]] 116 [[1], [1, 1], [6]] 117 [[1], [1, 1], [7]] 118 [[1], [1, 1], [8]] 119 [[1], [1, 1], [9]] 120 [[0], [1], [2]] 121 [[1], [1, 2, 1], [2]] 122 [[1], [2], [2, 2]] 123 [[1], [2], [3]] 124 [[1], [2], [4]] 125 [[1], [2], [5]] Number Has no >= 2 digit palindromes 9 true 169 true 12769 true 1238769 true 123498769 true 12346098769 true 1234572098769 true 123456832098769 true 12345679432098769 true 1234567905432098769 true 123456790165432098769 true 83071934127905179083 true 1320267947849490361205695 false
Phix
procedure show_all_palindromes(string s, integer longest=0) sequence res = {} for i=1 to length(s) do if longest=0 then res = append(res,{1,s[i..i]}) end if for j=0 to iff(i>1 and s[i-1]=s[i]?2:1) do integer rev = j, fwd = 1 while rev<i and i+fwd<=length(s) and s[i-rev]=s[i+fwd] do if longest=0 then res = append(res,{rev+fwd+1,s[i-rev..i+fwd]}) end if rev += 1 fwd += 1 end while if longest>0 then longest = max(longest,rev+fwd-1) end if end for end for if longest then printf(1,"%-26s %t\n",{s,longest<3}) else printf(1," %s %s\n",{s,join(vslice(unique(res),2))}) end if end procedure printf(1,"Number Palindromes\n") papply(apply(true,sprintf,{{"%d"},tagset(125,100)}),show_all_palindromes) constant tests = split_any("""9, 169, 12769, 1238769, 123498769, 12346098769, 1234572098769, 123456832098769, 12345679432098769, 1234567905432098769, 123456790165432098769, 83071934127905179083, 1320267947849490361205695"""," ,\n") printf(1,"\nNumber Has no >2 digit palindromes\n") papply(true,show_all_palindromes,{tests,1})
- Output:
Number Palindromes 100 0 1 00 101 0 1 101 102 0 1 2 103 0 1 3 104 0 1 4 105 0 1 5 106 0 1 6 107 0 1 7 108 0 1 8 109 0 1 9 110 0 1 11 111 1 11 111 112 1 2 11 113 1 3 11 114 1 4 11 115 1 5 11 116 1 6 11 117 1 7 11 118 1 8 11 119 1 9 11 120 0 1 2 121 1 2 121 122 1 2 22 123 1 2 3 124 1 2 4 125 1 2 5 Number Has no >2 digit palindromes 9 true 169 true 12769 true 1238769 true 123498769 true 12346098769 true 1234572098769 true 123456832098769 true 12345679432098769 true 1234567905432098769 true 123456790165432098769 true 83071934127905179083 true 1320267947849490361205695 false
Raku
A minor modification of the Longest palindromic substrings task. As such, works for any string, not just integers. <lang perl6>use Sort::Naturally;
sub getpal ($str) {
my @chars = $str.comb;
my @pal = flat @chars,
(1 ..^ @chars).map: -> \idx {
my @s;
for 1, 2 {
my int ($rev, $fwd) = $_, 1;
loop {
quietly last if ($rev > idx) || (@chars[idx - $rev] ne @chars[idx + $fwd]);
$rev = $rev + 1;
$fwd = $fwd + 1;
}
@s.push: @chars[idx - $rev ^..^ idx + $fwd].join if $rev + $fwd > 2;
last if @chars[idx - 1] ne @chars[idx];
}
next unless +@s;
@s
}
@pal.unique.sort({.chars, &naturally});
}
say 'All palindromic substrings including (bizarrely enough) single characters:'; put "$_ => ", getpal $_ for 100..125; put "\nDo these strings contain a minimum two character palindrome?"; printf "%25s => %s\n", $_, getpal($_).tail.chars > 1 for flat
9, 169, 12769, 1238769, 123498769, 12346098769, 1234572098769, 123456832098769, 12345679432098769, 1234567905432098769, 123456790165432098769, 83071934127905179083, 1320267947849490361205695, <Do these strings contain a minimum two character palindrome?></lang>
- Output:
All palindromic substrings including (bizarrely enough) single characters:
100 => 1 0 00
101 => 1 0 101
102 => 1 0 2
103 => 1 0 3
104 => 1 0 4
105 => 1 0 5
106 => 1 0 6
107 => 1 0 7
108 => 1 0 8
109 => 1 0 9
110 => 1 0 11
111 => 1 11 111
112 => 1 2 11
113 => 1 3 11
114 => 1 4 11
115 => 1 5 11
116 => 1 6 11
117 => 1 7 11
118 => 1 8 11
119 => 1 9 11
120 => 1 2 0
121 => 1 2 121
122 => 1 2 22
123 => 1 2 3
124 => 1 2 4
125 => 1 2 5
Do these strings contain a minimum two character palindrome?
9 => False
169 => False
12769 => False
1238769 => False
123498769 => False
12346098769 => False
1234572098769 => False
123456832098769 => False
12345679432098769 => False
1234567905432098769 => False
123456790165432098769 => False
83071934127905179083 => False
1320267947849490361205695 => True
Do => False
these => True
strings => False
contain => False
a => False
minimum => True
two => False
character => True
palindrome? => False
Wren
<lang ecmascript>import "/seq" for Lst import "/fmt" for Fmt import "/sort" for Sort
var substrings = Fn.new { |s|
var ss = []
var n = s.count
for (i in 0...n) {
for (j in 1..n-i) ss.add(s[i...i + j])
}
return ss
}
System.print("Number Palindromes") for (i in 100..125) {
var pals = []
var ss = substrings.call(i.toString)
for (s in ss) {
if (s == s[-1..0]) pals.add(s)
}
pals = Lst.distinct(pals)
var cmp = Fn.new { |i, j| (i.count - j.count).sign }
Sort.insertion(pals, cmp) // sort by length
Fmt.print("$d $3s", i, pals)
}
var nums = [
"9", "169", "12769", "1238769", "123498769", "12346098769", "1234572098769", "123456832098769", "12345679432098769", "1234567905432098769", "123456790165432098769", "83071934127905179083", "1320267947849490361205695"
] System.print("\nNumber Has no >= 2 digit palindromes") for (num in nums) {
var ss = substrings.call(num).where { |s| s.count > 1 }
var none = !ss.any { |s| s == s[-1..0] }
Fmt.print("$-25s $s", num, none)
}</lang>
- Output:
Number Palindromes 100 1 0 00 101 1 0 101 102 1 0 2 103 1 0 3 104 1 0 4 105 1 0 5 106 1 0 6 107 1 0 7 108 1 0 8 109 1 0 9 110 1 0 11 111 1 11 111 112 1 2 11 113 1 3 11 114 1 4 11 115 1 5 11 116 1 6 11 117 1 7 11 118 1 8 11 119 1 9 11 120 1 2 0 121 1 2 121 122 1 2 22 123 1 2 3 124 1 2 4 125 1 2 5 Number Has no >= 2 digit palindromes 9 true 169 true 12769 true 1238769 true 123498769 true 12346098769 true 1234572098769 true 123456832098769 true 12345679432098769 true 1234567905432098769 true 123456790165432098769 true 83071934127905179083 true 1320267947849490361205695 false