Task — Min diff

You are given an array of integers, @ints. Write a script to find the minimum difference between any two elements.

Examples

Example 1
Input: @ints = (1, 5, 8, 9)
Output: 1
1, 5 => 5 - 1 => 4
1, 8 => 8 - 1 => 7
1, 9 => 9 - 1 => 8
5, 8 => 8 - 5 => 3
5, 9 => 9 - 5 => 4
8, 9 => 9 - 8 => 1

Example 2
Input: @ints = (9, 4, 1, 7)
Output: 2
9, 4 => 9 - 4 => 5
9, 1 => 9 - 1 => 8
9, 7 => 9 - 7 => 2
4, 1 => 4 - 1 => 3
4, 7 => 7 - 4 => 3
1, 7 => 7 - 1 => 6

Analysis

I don't have much to say about this one as the code is almost the same as for task 1. Clearly, if we sort @ints the smallest gap will be between 2 consecutive elements, and the rest is just slightly different output.

And in case you wondered, see also Mind the gap.

Try it 

Try running the script with any input:

Your @ints =

example: -14, 23, -26, 14, -31

⤡

#!/usr/bin/perl

# Blog: http://ccgi.campbellsmiths.force9.co.uk/challenge

use v5.26;    # The Weekly Challenge - 2025-02-17
use utf8;     # Week 309 - task 2 - Min diff
use warnings; # Peter Campbell Smith
binmode STDOUT, ':utf8';

min_diff(1, 5, 8, 9);
min_diff(9, 4, 1, 7);

my @ints;
push @ints, int(rand(1000)) for 0 .. 11;
min_diff(@ints);

sub min_diff {
    
    my (@ints, $min_gap, $gap, $j, $where);
    
    # initialise
    @ints = sort {$a <=> $b} @_;    
    $min_gap = 1e9;
    
    # loop over @ints starting at the second element
    for $j (1 .. $#ints) {
        $gap = $ints[$j] - $ints[$j - 1];
        next if $gap >= $min_gap;
        
        # found the smallest so far
        $min_gap = $gap;
        $where = qq[$ints[$j - 1] and $ints[$j]];
    }
    
    say qq[\nInput:  \@ints = (] . join(', ', @_) . ')';
    say qq[Output: minimum difference is $min_gap between $where];
}

Output

Input:  @ints = (1, 5, 8, 9)
Output: minimum difference is 1 between 8 and 9

Input:  @ints = (9, 4, 1, 7)
Output: minimum difference is 2 between 7 and 9

Input:  @ints = (419, 772, 368, 569, 478, 471, 282, 858, 
   420, 910, 586, 746)
Output: minimum difference is 1 between 419 and 420