Question:
I am creating a function that receives an array of numbers and multiplies them but I have not found a viable solution.
This is what I have achieved so far:
var total = 0; var producto = [1,4,7]; function productoria(){ for (var f=0;f<producto.lenght;f++){ if(producto[f]!=0){ total = total + (producto[f]*total); } }return total; } console.log(productoria());
Answer:
Using reduce() is really short:
const producto = [1,4,7];
const res = producto.reduce((p,c)=>p*c);
console.log(res);The MDN documentation with examples here . Basically reduce would work like this:
arr.reduce(callback(acumulador, valorActual), valorInicial)
Where the acumulador stores the values that we want it to save when we want it to save them. The valorInicial , if we don't specify it, takes the first value of the array (in this example: 1). In the case of multiplication, each iteration we are multiplying the value of each element to the acumulador , it would work as the total variable of the question. The example without using the arrow function and using the return , would be:
const producto = [1, 4, 7]; const res = producto.reduce(function (acumulador, valorActual){ acumulador = acumulador * valorActual; return acumulador; } ); console.log(res);
The arrow function allows us to omit the return and the {} . In this case, the final value is a single number, but we could define an object or an array as the initial value and operate on the acumulador as we would an object or an array.