# Basic Algorithm Scripting - Mutations

Here is the problem:

I’m not sure what is wrong in my code, but it fails one of the tests in this challenge. If anyone has any input on what is going wrong without giving the answer away. Thanks!

my code:

``````function mutation(arr) {

var arr1 = arr[0].toLowerCase();

var arr2 = arr[1].toLowerCase();

arr1 = arr1.split("");

arr2 = arr2.split("");

for (var i= 0; i < arr2.length; i++){

return arr1.includes(arr2[i])

}

}

console.log(mutation(["hello", "hey"]));
//return true, should be false.
console.log(mutation(["ate", "date"]));
//returns false which is correct
``````

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I went ahead and fixed that. Thank you.

I added some console logs and I think you can see the problem, namely you just return the outcome of comparing the first letter:

``````function mutation(arr) {

var arr1 = arr[0].toLowerCase();

var arr2 = arr[1].toLowerCase();

arr1 = arr1.split("");

console.log(arr1);

arr2 = arr2.split("");

console.log(arr2)

for (var i= 0; i < arr2.length; i++){
console.log(arr2[i]);

return arr1.includes(arr2[i])

}

}

console.log(mutation(["hello", "hey"]));
//return true, should be false.
console.log(mutation(["ate", "date"]));
//returns false which is correct

``````

Console says:

``````[ 'h', 'e', 'l', 'l', 'o' ]
[ 'h', 'e', 'y' ]
h
true
[ 'a', 't', 'e' ]
[ 'd', 'a', 't', 'e' ]
d
false
``````