Welcome to Subscribe On Youtube

3931. Check Adjacent Digit Differences

Description

You are given a string s consisting of digits.

Return true if the absolute difference between every pair of adjacent digits is at most 2, otherwise return false.

The absolute difference between a and b is defined as abs(a - b).

 

Example 1:

Input: s = "132"

Output: true

Explanation:

  • The absolute difference between digits at s[0] and s[1] is abs(1 - 3) = 2.
  • The absolute difference between digits at s[1] and s[2] is abs(3 - 2) = 1.
  • Since both differences are at most 2, the answer is true.

Example 2:

Input: s = "129"

Output: false

Explanation:

  • The absolute difference between digits at s[0] and s[1] is abs(1 - 2) = 1.
  • The absolute difference between digits at s[1] and s[2] is abs(2 - 9) = 7, which is greater than 2.
  • Therefore, the answer is false.

 

Constraints:

  • 2 <= s.length <= 100
  • s consists only of digits.

Solutions

Solution 1: Simulation

We can simulate the process described in the problem: iterate through each pair of adjacent digits in the string and compute their absolute difference. If any pair has an absolute difference greater than 2, return $\text{false}$. If no such pair is found after the traversal, return $\text{true}$.

The time complexity is $O(n)$, where $n$ is the length of the string. The space complexity is $O(1)$.

  • class Solution {
    public boolean isAdjacentDiffAtMostTwo(String s) {
        for (int i = 1; i < s.length(); ++i) {
            if (Math.abs(s.charAt(i - 1) - s.charAt(i)) > 2) {
                return false;
            }
        }
        return true;
    }
}

  • class Solution {
public:
    bool isAdjacentDiffAtMostTwo(string s) {
        for (int i = 1; i < s.size(); ++i) {
            if (abs(s[i - 1] - s[i]) > 2) {
                return false;
            }
        }
        return true;
    }
};

  • class Solution:
    def isAdjacentDiffAtMostTwo(self, s: str) -> bool:
        return all(abs(x - y) <= 2 for x, y in pairwise(map(int, list(s))))


  • func isAdjacentDiffAtMostTwo(s string) bool {
	for i := 1; i < len(s); i++ {
		if abs(int(s[i-1])-int(s[i])) > 2 {
			return false
		}
	}
	return true
}

func abs(x int) int {
	if x < 0 {
		return -x
	}
	return x
}

  • function isAdjacentDiffAtMostTwo(s: string): boolean {
    for (let i = 1; i < s.length; i++) {
        if (Math.abs(Number(s[i]) - Number(s[i - 1])) > 2) {
            return false;
        }
    }
    return true;
}

All Problems

All Solutions