function strMultiply(a,b){
    const strA = String(a).split("").reverse().join(''); //i
    const strB = String(b).split("").reverse().join(''); // j
    const result = new Array(strA.length + strB.length).fill(0);
    
    
    for(let i=0 ;i<strA.length;i++){
        for(let j=0;j<strB.length;j++){
            const mult = +strA[i] * +strB[j];
            const sum = result[i+j] + mult
            result[i+j] = sum % 10;
            result[i+j + 1] += Math.floor(sum/10) 
       }
        
    }
    
    while(result[result.length -1]===0){
        result.pop()
    }
    
    return result.reverse().join("")
}