We have to create a function that takes in any number of arguments (Number literals), adds them together, and returns the product of digits when the answer is only 1 digit long.
For example −
If the arguments are −
16, 34, 42
We have to first add them together −
16+34+42 = 92
And then keep multiplying the digits together until we get a 1-digit number like this −
9*2 = 18 1*8 = 8
When we get the one-digit number, we have to return it from our function.
We will break this into two functions −
One function accepts a number and returns the product of its digits, we will use recursion to do so, let’s call this first function product().
Second function recursively calls this product() function and checks if the product happens to be 1 digit, it returns the product otherwise it keeps on iterating.
The code for this whole functionality will be −
Example
const recursiveMuliSum = (...numbers) => {
const add = (a) => a.length === 1 ? a[0] : a.reduce((acc, val) => acc+val);
const produce = (n, p = 1) => {
if(n){
return produce(Math.floor(n/10), p*(n%10));
};
return p;
};
const res = produce(add(numbers));
if(res > 9){
return recursiveMuliSum(res);
}
return res;
};
console.log(recursiveMuliSum(16, 28));
console.log(recursiveMuliSum(16, 28, 44, 76, 11));
console.log(recursiveMuliSum(1, 2, 4, 6, 8));Output
The output in the console will be −
6 5 2