SereneCrimsonVoxel-1 created by hillal20 - https://repl.it/@hillal20/SereneCrimsonVoxel-1

main.js

  
let geant = (a,b)=>{
let big = (x)=>{
 let bill =  (x)=>{
let fill = []
   for (  let i = 0 ; i <= x; i ++){
            if ( x % i === 0 ){
                fill.push(i)
            }
   }

  return fill;
 }

  let result = bill(x)
  
  
  
  let a = 1 
 let arr = []
  let dill = ( result , x )=>{
     
        if ( a === result.length ){
         
          return arr;
        }
        if ( x === 1 ){
         
          return arr;
        }
        
         if( x % result[a] === 0 ){
              arr.push(result[a])
             
              x = x/result[a]
            
              dill(result, x )
         }
         else{
           
             a++
        dill( result , x )
        }
        
     }

  
    dill( result, x)
  return arr;
 }
   const A = big(a)
   const B = big(b)
 
 
  const  newArr = [];
    for( let i = 0 ; i < A.length; i ++){
      if( B.includes(A[i]) &&  !newArr.includes(A[i])){
      newArr.push(A[i])
      }
     
    }
  
    let total = 1;
    for( let i = 0 ; i < newArr.length; i ++){
        total *= newArr[i]
    }
    return total 
    }
     const final = geant(90,30)
    console.log(final)