find_if_a_string_is_rotated.md

Find if a String is Rotated

Find if a String is Rotated

To check if one string is a rotation of another, concatenate the second string with itself and check if the first string is a substring of the concatenated string.

Algorithm:

1. Concatenate the second string with itself.
2. Check if the first string is a substring of the concatenated string.
3. Return true if it is a substring, false otherwise.

Example:

function isRotated(str1, str2) {
    if (str1.length !== str2.length) return false;
    return (str2 + str2).includes(str1);
}

// Example usage
console.log(isRotated('abc', 'bca')); // Output: true
console.log(isRotated('abc', 'acb')); // Output: false

This method has a time complexity of O(n), where n is the length of the string.

Tags: intermediate, JavaScript, Strings, Algorithm