Smallest Common Multiple

1

Hello,

I wrote a script for the Smallest Common Multiple project but it seems that isn’t working for bigger numbers.
Probably because the loop is taking too long.

Here is to code:

function smallestCommons(arr) {
  arr.sort(function(a,b){
    return a-b;
  });
  
  var s = arr[0];
  var b = arr[1];
  
  var idx = 1;
  var found = false;
  
  while(!found){
    var k = 0;
    for(s = arr[0]; s<=b; s++){
      if(idx%s === 0)
        k++;
    }
    
    if(k === b)
      break;
    
    idx++;
  }
  return idx;
}

smallestCommons([1,13]);

I know my logic is wrong. But this is what I could get up to this point! :stuck_out_tongue:
I know it works, but it gets stuck in the middle somewhere xD.

2

The best way to solve this is to study up on the euclidean algorithm a bit.
Its basically lcm(a, b) = gcd(a, b)/a * b

I’d advise you find the code for gcd for a start, then use it to find lcm.

3

This is what I did at the end… I’ve learned how it works with lcm and gcd :slight_smile:

P.S. It’s lcm(a,b) = (a*b) / gcd(a,b) as far as I know :smiley:

4

How I would do it now

Function lcm(a, b){
let i = a;
While(i<999999999){
If (I % b === 0) then {
Return I;
} else {
 I += a;
}
}
Return "greater than 999999999";
}

Celphone, forgive the changing case.

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