How to resolve the algorithm Self-describing numbers step by step in the zkl programming language

Published on 12 May 2024 09:40 PM
#Zkl

How to resolve the algorithm Self-describing numbers step by step in the zkl programming language

Table of Contents

Problem Statement

There are several so-called "self-describing" or "self-descriptive" integers. An integer is said to be "self-describing" if it has the property that, when digit positions are labeled 0 to N-1, the digit in each position is equal to the number of times that that digit appears in the number. For example,   2020   is a four-digit self describing number:

Self-describing numbers < 100.000.000  are:     1210,   2020,   21200,   3211000,   42101000.

Let's start with the solution:

Step by Step solution about How to resolve the algorithm Self-describing numbers step by step in the zkl programming language

Source code in the zkl programming language

fcn isSelfDescribing(n){
   if (n.bitAnd(1)) return(False); // Wikipedia: last digit must be zero
   nu:= n.toString();
   ns:=["0".."9"].pump(String,nu.inCommon,"len"); //"12233".inCommon("2")-->"22"
   (nu+"0000000000")[0,10] == ns;  //"2020","2020000000"
}

//[1..0x4_000_000].filter(isSelfDescribing).println();
const N=0d500_000;
[1..0d100_000_000, N] // chunk and thread, 200 in this case
   .apply(fcn(n){ n.filter(N,isSelfDescribing) }.future)
   .filter().apply("noop").println();

You may also check:How to resolve the algorithm 100 doors step by step in the XPL0 programming language
You may also check:How to resolve the algorithm Sorting algorithms/Merge sort step by step in the Standard ML programming language
You may also check:How to resolve the algorithm Text processing/1 step by step in the PowerShell programming language
You may also check:How to resolve the algorithm Address of a variable step by step in the Sidef programming language
You may also check:How to resolve the algorithm Find limit of recursion step by step in the Modula-2 programming language