How tall are the monoliths?

Question

Here is an example of an input of monoliths. There are 4 in this example.

  _
 | |        _
 | |  _    | |
 | | | |   | |     _
_| |_| |___| |____| |_

The first monolith is 4 units high, the second is 2, the third is 3, and the last is 1.

The task

Your program should output the heights of the monoliths in order from left to right. The output format can be in any sort of list or array.

Notes

• The input can be taken as any dimensional string, list of strings, or list of characters.
• This is code-golf, so lowest bytes wins.
• You are to assume that monoliths always have the same width, and are always at least 1 _ away from another.
• They can come in any height, and in any quantity.

I/O

  _
 | |        _
 | |  _    | |
 | | | |   | |     _
_| |_| |___| |____| |_   >> [4,2,3,1]

           _
          | |
  _       | |
 | |  _   | |  _
_| |_| |__| |_| |_   >> [2,1,4,1]


 _   _   _ 
| |_| |_| |_____   >> [1,1,1]

____________________   >> undefined behavior

 _
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |   >> [11]

     _       _       _       _       _
 _  | |  _  | |  _  | |  _  | |  _  | |
| |_| |_| |_| |_| |_| |_| |_| |_| |_| |  >> [1,2,1,2,1,2,1,2,1,2]

Answer 1

Jelly, (8?) 9 bytes

Ỵ=”|Sḟ0m2

A monadic link accepting a list of characters as specified and returning a list of integers.

Note: 8 bytes if a list of strings, one per line, was really intended to be an allowed input format - just remove the Ỵ.

Try it online!

How?

Ỵ=”|Sḟ0m2 - Link: list of characters, s
Ỵ         - split at newlines
  ”|      - literal '|'
 =        - equals (vectorises)
    S     - sum (vectorises, hence counts the number of '|' in every column)
     ḟ0   - filter out zeros (only keep the results from the sides of the towers)
       m2 - modulo index with 2 (keep only the left side measurements)

Answer 2

Jelly, 11 bytes

ỴṚZi€”_ỊÐḟ’

Try it online!

Answer 3

JavaScript (ES6), 79 78 bytes

-1 byte thanks to @Shaggy

a=>a.map((b,i)=>b.replace(/_/g,(_,j)=>o[j]=a.length-i-1),o=[])&&o.filter(x=>x)

Takes input as an array of strings.

Test Snippet

f=
a=>a.map((b,i)=>b.replace(/_/g,(_,j)=>o[j]=a.length-i-1),o=[])&&o.filter(x=>x)
I.value="           _\n          | |\n  _       | |\n | |  _   | |  _\n_| |_| |__| |_| |_"

<textarea id=I rows=7 cols=30></textarea><br><button onclick="O.value=`[${f(I.value.split`\n`).join`, `}]`">Run</button> <input id=O disabled>

Answer 4

05AB1E, 11 bytes

|Rζ'_δkJ®0‚K

Try it online!

ζ has been replaced by .Bø on TIO since it hasn't been pulled there yet.

Answer 5

Dyalog APL, 29 bytes

{0~⍨↑+/(⌈/⍴¨⍵)↑¨(⍳≢⍵)×⌽⍵='_'}

Run with ⎕IO←0.

Try it online!

How?

⌽⍵='_' - where ⍵ is '_', top lines first

×- multiply by ...

(⍳≢⍵) - the range of ⍵ (zero indexed)

↑¨ - for each line, pad with zeros by ...

(⌈/⍴¨⍵) - the maximal length

↑+/ - sum the rows zipped and flatten

0~⍨ - removes zeros

Answer 6

C++, 171 169 bytes

#import<vector>
#import<iostream>
int f(std::vector<std::string>s){for(int a,j,i=0,k=s.size()-1;a=s[k][i];++i)if(a==32){for(j=0;(a=s[k-++j][i])-95;);std::cout<<j<<" ";}}

Try it online!

C++ (GCC), 150 bytes

Thanks to @aschepler!

#import<vector>
#import<iostream>
int f(auto s){for(int a,j,i=0,k=s.size()-1;a=s[k][i];++i)if(a==32){for(j=0;(a=s[k-++j][i])-95;);std::cout<<j<<" ";}}

Try it online!

Answer 7

Python 2, 75 bytes

lambda s:[x.index('_')for x in map(None,*s.split('\n')[::-1])if'_'in x[1:]]

Try it online!

Answer 8

Japt, 11 bytes

z ·mb'_ fw0

Test it online!

Explanation

z ·mb'_ fw0   : Implicit input
z             : Rotate the input clockwise. This puts the "floor" against the left side.
  ·           : Split the 2D string into lines.
   m          : Replace each column (now row) X with
    b'_       :   the index of '_' in X (0-indexed). This gives us the output list, with
              :   0's and -1's mixed in representing the columns that are not monoliths.
        f     : Take only the items X where
         w0   :   max(X, 0) is truthy. Since 0 is falsy, this removes anything <= 0.
              : Implicit: output result of last expression

Answer 9

PowerShell, 133 bytes

param($s)$r=,0*($l=($s=$s-replace'\| \|',' 1 ')[0].Length);1..$s.Count|%{$z=$_-1;0..($l-1)|%{$r[$_]+=(''+$s[$z][$_]-as[int])}};$r-ne0

Looks like it's not very competitive; it does a regex replace to turn the towers into columns of 1, makes an array of 0 the length of the input string, then steps through the lines adding up the 1s.

Tests ready to run:

$s1 = @'
  _                   
 | |        _         
 | |  _    | |        
 | | | |   | |     _  
_| |_| |___| |____| |_
'@-split"`r?`n"


$s2 = @'
 _
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| | 
'@-split"`r?`n"

$s3 = @'
           _      
          | |       
  _       | |           
 | |  _   | |  _   
_| |_| |__| |_| |_ 
'@-split"`r?`n"


$s4 = @'
 _   _   _      
| |_| |_| |_____ 
'@-split"`r?`n"

$s5 = @'
     _       _       _       _       _ 
 _  | |  _  | |  _  | |  _  | |  _  | |
| |_| |_| |_| |_| |_| |_| |_| |_| |_| | 
'@-split"`r?`n"

Answer 10

Retina, 48 38 bytes

^
¶
{`(¶.*)*¶_(.*¶)+
$#2 $&
}`¶.
¶
G`.

Try it online! Link includes first example. Explanation: A line is prefixed which will collect the results. As each column is repeatedly deleted in turn, those that contains a _ above ground level have the the number of remaining lines in the column counted. Finally the now blank lines are deleted. Edit: Saved 10 bytes thanks to inspriation from @FryAmTheEggman.

Answer 11

Java 8 - 229 Bytes 213 Bytes

s->{Map<Integer,Integer> m=new TreeMap();String[] l=s.split("\n");for(int i=0,j=-1;i<l.length-1;++i){s=l[i];while((j=s.indexOf("_",j+1))>=0){m.put(j,i);}}for(int i:m.values()){System.out.print(l.length-i-1+",");}}

Try it online!

Ungolfed:

public static void foo(String input)
{
    Map<Integer, Integer> map = new TreeMap(); // Raw types!!
    String[] lines = input.split("\n");

    for (int i = 0, j = -1; i < lines.length - 1; ++i)
    {
        input = lines[i];

        while ((j = input.indexOf("_", j + 1)) >= 0)
        {
            map.put(j, i);
        }
    }

    for(int i:map.values())
    {
        System.out.print(lines.length - i - 1 + ",");
    }
}

Woo, first post. Any help improving it would be great. I know I can get rid of that indexOf written twice. Knew it! I toyed with the idea of changing the types in the map from Integer to Long but I think that's a dead end.

---

_{I know there is a much, much better Java 8 solution already, but that takes char[][] as input which I think is easier to work with in this case than String.}

Answer 12

Java 8, 133 117 116 114 bytes

a->{for(int l=a.length-1,i=0,j;i<a[0].length;i++)if(a[l][i]<33){for(j=0;a[j][i]<33;j++);System.out.print(l-j+",");}}

Takes the input as a String[] char[][] (← saves 16 bytes).
-2 bytes in exchange for less readable output thanks to @OlivierGrégoire by changing print(l-j+",") to println(l-j).

Explanation:

Try it here.

a->{                         // Method with character 2D-array parameter and no return-type
  for(int l=a.length-1,      //  Length of the 2D char-array - 1
      i=0,j;                 //  Index-integers
    i<a[0].length;i++)       //  Loop (1) over the 2D char-array
    if(a[l][i]<33){          //   If the base of the current column is a space
      for(j=0;a[j][i]<33;    //    Loop (2) over the cells in this column as long as
                             //    we encounter spaces (from top to bottom)
        j++                  //     And increase `j` every time, to go down the column
      );                     //    End of loop (2)
      System.out.println(l-j);
                             //    Print the amount of rows - `j`
    }                        //   End of if-block
                             //  End of loop (1) (implicit / single-line body)
}                            // End of method

Answer 13

Haskell, 75 74 bytes

import Data.List;f=filter(>0).map(length.fst.span(<'!').reverse).transpose

The input is expected as a list of strings (rowwise).

Answer 14

APL (Dyalog), 14 bytes

0~⍨⍳∘≢+.×'_'=⊖

with ⎕IO←0

Try it online!

---

This function train equivalent to {((⍳≢⍵)+.×('_'=⊖⍵))~0}

Answer 15

MATL, 12 bytes

&nxG2\&fx-Xz

Input is a char matrix, with ; as row separator.

Try it online! Or verify all test cases.

Answer 16

C#, 150 144 137 bytes

using System.Linq;a=>a.SelectMany((i,h)=>i.Select((c,w)=>new{c,w,d=a.Length-1-h}).Where(o=>o.c==95&o.d>0)).OrderBy(o=>o.w).Select(o=>o.d)

Full/Formatted version:

using System;
using System.Collections.Generic;
using System.Linq;

class P
{
    static void Main()
    {
        Func<char[][], IEnumerable<int>> f = a =>
            a.SelectMany((i, h) => i.Select((c, w) => new { c, w, d = a.Length - 1 - h })
                                    .Where(o => o.c == 95 & o.d > 0))
             .OrderBy(o => o.w)
             .Select(o => o.d);

        Console.WriteLine(string.Concat(f(new char[][]
        {
            "  _                 ".ToArray(),
            " | |       _        ".ToArray(),
            " | |  _   | |       ".ToArray(),
            " | | | |  | |    _  ".ToArray(),
            "_| |_| |__| |___| |_".ToArray(),
        })));

        Console.ReadLine();
    }
}

Answer 17

MATL, 10 bytes

ooYssqtO>)

Input is a padded character matrix.

Try it online!

Answer 18

Mathematica, 48 47 39 bytes

Last/@(Reverse@Most@#~Position~"_")&

Try it online!

Function which expects a rectangular array of characters. Takes Most of the array (all but the last row), Reverses it, then takes the Transpose*, then finds all Positions at which the _ character appears. The relevant heights are the Last elements of each Position.

*  is the 3 byte private use character U+F3C7 which represents \[Transpose] in Mathematica. Note that this doesn't work in Mathics, so the TIO link just uses Transpose.

Answer 19

Ruby, 82 bytes

Takes in a list of lines.

->l{l.map! &:chars;(l.pop.zip(*l).map{|s|s.join.count ?|}-[i=0]).select{0<1&i+=1}}

Try it online!

Answer 20

SOGL V0.12, 9 bytes

I{ _WH╥?O

Try it Here!
Takes input as an array of arrays of strings (characters).

Explanation:

I          rotate the array clockwise
 {         for each element
   _       push "_"
    W      get its index in the array (0 if not found, 1 if its the ground, >1 if its what we need)
     H     decrease that
      ╥    palindromize (duplicates the number, if it's <0, then errors and pushes 0, if =0, pushes 0, if >0, then pushes the number palindromized (always truthy))
       ?   if that, then
        T  output in a new line the original decreased index

Answer 21

JavaScript (ES6), 108 104 88 bytes

Saved 16 bytes thanks to @JustinMariner

i=>i.map((s,h)=>{while(t=r.exec(s))m[t.index]=i.length-h-1},m=[],r=/_/g)&&m.filter(e=>e)

Input taken as an array of strings

let input = [
'  _',
' | |           _',
' | |  _   _   | |',
' | | | | | |  | |     _',
'_| |_| |_| |__| |____| |_'
]

let anonymousFunction =
i=>i.map((s,h)=>{while(t=r.exec(s))m[t.index]=i.length-h-1},m=[],r=/_/g)&&m.filter(e=>e)

console.log(anonymousFunction(input))

Answer 22

CJam, 15 14 bytes

^{1 byte saved thanks to @BusinessCat}

{W%z'_f#{0>},}

This is a block that takes an array of strings on the stack and outputs an array.

Explanation:

W%    e# Reverse
z     e# Zip
'_f#  e# Get the index of '_' in each element (-1 if not found)
{0>}, e# Filter where positive

Answer 23

Pip, 18 17 bytes

15 bytes of code, +2 for -rp flags.

_FI_@?'_MRVgZDs

Takes input from stdin. Try it online!

Explanation

                 g is list of lines from stdin (-r flag); s is space
         RVg     Reverse g
            ZDs  Zip (transpose), filling gaps with a default char of space
        M        Map this function:
   _@?'_          Index of _ in each line (or nil if it doesn't appear)
_FI              Filter, keeping only the truthy (nonzero, non-nil) values
                 Autoprint in repr format (-p flag)

Answer 24

Pyth, 19 15 14 bytes

f>T0mx_d\_.tQd

Test it online! The input is a list of lines.

Explanations

          .tQd     # Transpose, pad with spaces
    mx_d\_         # For each line, reverse it, find the position of "_" (-1 if not found)
f>T0               # Filter on positions greater than zero

Answer 25

Octave, 31 bytes

@(a)(s=sum(a>95))(s>0)(1:2:end)

Takes a 2D array of chars as input.

Verify all test cases!

Answer 26

Perl 6, 65 bytes

{m:ex/^^(\N+)_([\N*\n]+:)/.sort(*[0].chars).map(+*[1].comb("
"))}

Try it online!

• m:exhaustive/^^(\N+)_([\N*\n]+:)/ searches the input string for all underscores, and returns a match object for each, where the first capturing parentheses contain the preceding part of the line on which the underscore is found, and the second capturing parentheses contain the entire rest of the string. The rest of the string must contain at least one newline, so we don't count the underscores at ground level. The :exhaustive flag allows these matches to overlap.
• .sort(*[0].chars) sorts these match objects by the number of characters in the part of the line preceding each underscore. This orders them left-to-right.
• .map(+*[1].comb("\n")) maps each match object to the number of newline characters in the part of the input string trailing each underscore--that is, the height. The \n is an actual newline character, saving one byte.

Answer 27

Python 2, 58 bytes

lambda l:[s.index('_')+1for s in zip(*l[-2::-1])if'_'in s]

Try it online!

Taking input as list of strings.

Answer 28

PHP, 119 bytes

function($s){$r=array_map(null,...$s);foreach($r as$k=>&$v)if($v=array_count_values($v)['|'])echo($v+$r[$k+2]=0)." ";};

Let's break this down! Our input here is a 2D array of chars.

$r=array_map(null,...$s) // Neat little snippet to transpose the array

foreach($r as$k=>&$v)    // Loop through the array, grabbing each row of our 2D array 
(which is now each column of the monolith)

if($v=array_count_values($v)['|']) // Count the number of '|' characters in the column 
(which is the height of our monolith), and if it's greater than 0 (truthy in PHP)...

echo($v+$r[$k+2]=0)." "; // Output that number, and simultaneously set the row 2 indices
                            down to null (to remove duplicate values)

Answer 29

Japt, 9 bytes

Takes input as an array of lines.

Õ®x2 èSÃf

Try it (header splits input string to array) or run all test cases

Õ®x2 èSÃf     :Implicit input of array
Õ             :Transpose
 ®            :Map
  x2          :  Trim left
     è        :  Count
      S       :    Spaces
       Ã      :End map
        f     :Filter

Answer 30

Jelly, 9 bytes

ṖZ=”_UT€F

Try it online!

Unfortunately, Jonathan Allan's answer is still shorter, as I assume input is a list of lines, so don't count the Ỵ. However, I reckon this is an interesting enough approach to post

How it works

ṖZ=”_UT€F - Main link. Takes a list of lines L on the left
Ṗ         - Remove the last line
 Z        - Transpose
  =”_     - Check each character for equality with "_"
     U    - Reverse each row
       €  - For each row
      T   - Yield the indices of 1
        F - Flatten