# Digits of a number when iterating through a loop in JavaScript

Suppose that when iterating over numbers, we want to get some digit from these numbers. For example, we want to make a number be displayed on the console if its first digit is `1` or `2`.

I remind you that you can’t refer to the characters of a number directly, that is, it won’t work like this:

`for (let i = 1; i <= 100; i++) { if (i[0] == 1 || i[0] == 2) { // that won't work console.log(i); } }`

First you need to convert the number to a string and then get a certain character of the returned string, like this:

`for (let i = 1; i <= 100; i++) { let str = String(i); // converting number to string if (str[0] === '1' || str[0] === '2') { console.log(i); } }`

Loop through the numbers from `10` to `1000` and output the first digit of each number to the console.

Loop through the numbers from `10` to `1000` and output the sum of the first and second digits of each number to the console.

Loop through the numbers from `10` to `1000` and output those numbers whose first digit is equal to `1`.

Loop through the numbers from `10` to `1000` and display those numbers whose sum of the first two digits is `5`.

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