Coding Problem : Score of a String

Problem Name: Score of a String

Problem Statement:
Given a string `s`, calculate the score of the string where the score is defined as the sum of absolute differences between each pair of consecutive characters.

Input:
A single string `s` consisting of lowercase English letters.

Output:
An integer representing the score of the string.

Constraints:
- The length of the string `s` will be between 1 and 1000.

Example:
Input: "abcd"
Output: 3
Explanation: The score is calculated as |b-a| + |c-b| + |d-c| = 1 + 1 + 1 = 3.

Platforms:

• LeetCode
• HackerRank

Companies:

• Google
• Facebook

Topics Covered:
Strings, Mathematics, Loops, Absolute Differences, Character Manipulation

Solution:

Algorithm:
1. Initialize a variable `sum` to 0.
2. Loop through the string from the second character to the end.
3. For each character, calculate the absolute difference with the previous character and add it to `sum`.
4. Return the `sum` as the score of the string.

Code Implementation:

C:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int scoreOfString(char* s) {
    int sum = 0;
    for (int i = 1; i < strlen(s); i++) {
        sum += abs(s[i] - s[i-1]);
    }
    return sum;
}

        

C++:

class Solution {
public:
    int scoreOfString(string s) {
        int sum = 0;
        for(int i = 1; i < s.size(); i++) {
            sum += abs(s[i] - s[i-1]);
        }
        return sum;
    }
};
                

Java:

class Solution {
    public int scoreOfString(String s) {
        int sum = 0;
        for (int i = 1; i < s.length(); i++) {
            sum += Math.abs(s.charAt(i) - s.charAt(i - 1));
        }
        return sum;
    }
}
                

Python:

class Solution:
    def scoreOfString(self, s: str) -> int:
        return sum(abs(ord(s[i]) - ord(s[i - 1])) for i in range(1, len(s)))
                

Complexity Analysis:

Case	Time Complexity	Space Complexity
Worst Case	O(n)	O(1)
Average Case	O(n)	O(1)
Best Case	O(n)	O(1)