为什么我的 for 循环只将第一个结果返回到 JavaScript 中的数组？

Question

I am attempting to add the results of doubling every other number in an array to a new array. However the code only seems to be pushing the first index that is doubled. I assume the problem is with the.push line but I am not sure. Thanks for any help!

Here is the code I have:

const addTwoDigits = n => {
  return n % 10 + Math.floor(n / 10);
}

const validateCred = array => {
          let sumNums = []
          let i = array.length - 2
          while (i > 0) {
              let doubleNum = (array[i] * 2)
              if (doubleNum > 9) {
                let addedNum = addTwoDigits(doubleNum)
                sumNums.push(addedNum)
              } else {
                sumNums.push(doubleNum)
              }
              i--; 
              return sumNums;
        }
}

const testArray = [4, 2, 1, 6, 5, 7, 5]
console.log(validateCred(testArray));

I was hoping the sumNums array would contain every other digit doubled (starting with '' in the test array and moving left) but it only returns [ 5 ].

Answer 1

You returned the value in the loop. When the compiler comes in loop then first time it returns the value and break the loop.

const addTwoDigits = n => {
  return n % 10 + Math.floor(n / 10);
}

const validateCred = array => {
          let sumNums = []
          let i = array.length - 2
          while (i > 0) {
              let doubleNum = (array[i] * 2)
              if (doubleNum > 9) {
                let addedNum = addTwoDigits(doubleNum)
                sumNums.push(addedNum)
              } else {
                sumNums.push(doubleNum)
              }
              i--; 
        }
        return sumNums;
}

const testArray = [4, 2, 1, 6, 5, 7, 5]
console.log(validateCred(testArray));

Your can try this code.