Print all even values in all object key end with odd value

Question

I want to print all even values in all object key end with odd value but the coding I made just now is only specified for arr1, arr3, and arr5. Can anyone suggest me how to fix 'let oddArr' method (maybe in loop) so that when I changed arr1 into arr7, the result would be the same.

var num = {
    arr1 : [1, 2, 3, 4, 5, 6, 7, 8, 9, 10],
    arr2 : [11, 12, 13, 14, 15, 16, 17, 18, 19, 20],
    arr3 : [21, 22, 23, 24, 25, 26, 27, 28, 29, 30],
    arr4 : [31, 32, 33, 34, 35, 36, 37, 38, 39, 40],
    arr5 : [41, 42, 43, 44, 45, 46, 47, 48, 49, 50],
    };

    let oddArr = [...num.arr1, ...num.arr3, ...num.arr5] //need some correction here
    let evenNum = oddArr.filter(number => number % 2 == 0);

    console.log(evenNum.toString());
    
    //help me fix 'let oddArr' (maybe in loop method) so that when I changed the object of the array (e.g: arr1 -> arr7) it would come out with the same result 
    
    //the result/output should be 2,4,6,8,10,22,24,26,28,30,42,44,46,48,50 based on var num

Answer 1

You can try like below using for in loop and it works with any last character as odd.

var num = {
  arr1: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10],
  arr2: [11, 12, 13, 14, 15, 16, 17, 18, 19, 20],
  arr3: [21, 22, 23, 24, 25, 26, 27, 28, 29, 30],
  arr4: [31, 32, 33, 34, 35, 36, 37, 38, 39, 40],
  arr7: [41, 42, 43, 44, 45, 46, 47, 48, 49, 50]
};

let oddArr = [];
for (let key in num) {
  if (key.charAt(key.length - 1) % 2 !== 0) {
    oddArr = [...oddArr, ...num[key]];
  }
}

let evenNum = oddArr.filter((number) => number % 2 === 0);

console.log(evenNum.toString());