# Issue with an 'Challenge Project: Credit Card Checker' project

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const valid1 = [4, 5, 3, 9, 6, 7, 7, 9, 0, 8, 0, 1, 6, 8, 0, 8];

'const validateCred = (arr)=>{
let newArray=;
for (var i = arr.length - 1; i >= 0; i–) {
if(i%2==0){
newArray.push(arr[i])
}else{
newArray.push(arr[i]*2)
}
}

console.log(newArray)
}

console.log(valid1)
validateCred(valid1)

The output of my code so far:

Output:

[ 4, 5, 3, 9, 6, 7, 7, 9, 0, 8, 0, 1, 6, 8, 0, 8 ]
[ 16, 0, 16, 6, 2, 0, 16, 0, 18, 7, 14, 6, 18, 3, 10, 4 ]

I am not sure how to subtract -9 once the value in the array is double and greater than 9. Am I going in the right direction? Here is the link to the exercise I am working on.

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You could make another variable to do that.

}else{
newArray.push(arr[i]*2)
}

but you could expand that to be

}else{
let x = arr[i] * 2;
if(x > 9){
x = x - 9;
}
newArray.push(x);
}