How to iterate over a range and an array of data and set the iterated array values until there’s no data using GAS?

This may seem simple to you, but well….here I am.

The code below sets the last value to all cells in the rangeList and I’d like to know where the flaw is:

const rngs = ["A10", "F10", "J10", "A12", "F12", "J12"];
const rangeList = sheetVendSobEnc.getRangeList(rngs).getRanges();
let coresPartes = ["Alca", "Mangas"]//Splits the value into a 1D array
  for (let a = 0; a < rangeList.length; a++) {
    for (let n = 0; n < coresPartes.length; n++) {
      if(coresPartes[n] != ''){
      rangeList[a].setValue(coresPartes[n])
      }
    }
  }

Thank you in advance!