Is Reverse Degree of a String easy or hard?

Reverse Degree of a String is considered an easy problem. It focuses on basic string traversal, character arithmetic, and index-based calculations rather than complex algorithms or data structures.

Reverse Degree of a String Python/Java solution

The solution in Python or Java iterates through the string, calculates the reverse alphabet value using character arithmetic ('z' - c + 1), multiplies it by the index (i + 1), and accumulates the sum. The implementation is O(n) time and O(1) space in all major languages including Python, Java, C++, Go, and TypeScript.

How to solve Reverse Degree of a String in O(n)?

Iterate through the string from left to right. For each character at index i, compute its reverse alphabet value using ('z' - s[i] + 1), multiply it by (i + 1), and add it to a running total. Since every character is processed once, the algorithm achieves O(n) time complexity.

What is the best approach for Reverse Degree of a String?

The best approach is a single-pass simulation that computes each character's reverse alphabet value using ASCII arithmetic: ('z' - c + 1). Multiply that value by the character's 1-based index and accumulate the result. This solution runs in O(n) time and O(1) space.

Is Reverse Degree of a String asked at Google/Amazon/Meta?

Problems like Reverse Degree of a String appear in coding screens or online assessments as warm-up string manipulation questions. They test understanding of ASCII arithmetic, indexing, and basic iteration rather than advanced algorithms.

What data structure is used in Reverse Degree of a String?

No complex data structure is required. The problem is solved using simple string traversal and arithmetic operations. Some implementations use a small lookup array or map for reverse alphabet values, but it is not necessary.

What is the time complexity of Reverse Degree of a String?

The optimal solution runs in O(n) time because the algorithm scans the string once and performs constant-time arithmetic for each character. Space complexity is O(1) since only a few variables are required.

Description Hints 1 Solution Video 4:55

3498. Reverse Degree of a String

Easy91.9% acceptance2 companies

Given a string s, calculate its reverse degree.

The reverse degree is calculated as follows:

For each character, multiply its position in the reversed alphabet ('a' = 26, 'b' = 25, ..., 'z' = 1) with its position in the string (1-indexed).
Sum these products for all characters in the string.

Return the reverse degree of s.

Example 1:

Input: s = "abc"

Output: 148

Explanation:

Letter	Index in Reversed Alphabet	Index in String	Product
`'a'`	26	1	26
`'b'`	25	2	50
`'c'`	24	3	72

The reversed degree is 26 + 50 + 72 = 148.

Example 2:

Input: s = "zaza"

Output: 160

Explanation:

Letter	Index in Reversed Alphabet	Index in String	Product
`'z'`	1	1	1
`'a'`	26	2	52
`'z'`	1	3	3
`'a'`	26	4	104

The reverse degree is 1 + 52 + 3 + 104 = 160.

Constraints:

1 <= s.length <= 1000
s contains only lowercase English letters.

Asked at 2 companies

Capgemini

Google

Topics

Simulation String

Hints open one at a time

Hint 1

Simulate the operations as described.

4:55

Still stuck?Read the written solution, or watch a walkthrough.

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1class Solution:
2    def reverseDegree(self, s: str) -> int:
3        

Starter codePython 3Spaces: 4

Examples

Case 1Case 2

Input

"abc"

Input

"zaza"

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