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# I can't increase the value with =+, it give me the value NaN. Help!

This is my code:

```var score = 0;

// USER QUESTIONS!

var choice1 = prompt('DOTA2: What heroe\'s ultimate is called PULSE NOVA?');
if ( choice1.toUpperCase() === 'LESHRAC' ) {
score += 1 && alert('Congratulation! You got one right!');
document.write('<p>Question 1: Correct! </p>');
} else {
alert('Auch! That\'s incorrect, but I\'m sure you know the next one!');
document.write('<p>Question 1: False! </p>');
}
```

What I'm hoping is to increase the value of 'score' with +1 for each correct answer. At the end I will try to give a medal based on the value of 'score'. But what I wrote so far doesn't work.... it tells me score is a NaN when i doc.write it... How can I make this work ?

Hi Sorin! I believe the problem lies in this line.

```score += 1 && alert('Congratulation! You got one right!');
```

The '&&' is what is called a logical operator and is used to compare true/false statements. If you eliminate that, and split that line into two like this, it should work alright!

```score += 1;
alert('Congratulations! You got one right!');
```

Hopefully that answers your question, have a great day!

Yup, that was it! Thanks for the explanation!

No problem! Have a great day and happy coding! :)