Is Remove Digit From Number to Maximize Result easy or hard?

The problem is classified as Easy on LeetCode. The main challenge is recognizing the greedy insight that removing a digit before a larger neighbor increases the final number. Once that observation is made, the implementation becomes straightforward.

Remove Digit From Number to Maximize Result Python/Java solution

In both Python and Java, the greedy solution scans the string and removes the first occurrence of the digit whose next digit is larger. If such a position is not found, remove the last occurrence. The implementation typically uses substring operations or slicing and runs in O(n) time.

How to solve Remove Digit From Number to Maximize Result in O(n)?

Iterate through the number string and check every position where the digit matches the target digit. If the next digit is greater than the current digit, remove that occurrence immediately and return the result. This greedy choice maximizes the number as early as possible. If no such position exists, remove the last occurrence of the digit.

What is the best approach for Remove Digit From Number to Maximize Result?

The greedy approach is the best solution. Scan the string and remove the first occurrence of the target digit where the next digit is larger. This increases the value because the larger digit shifts to a more significant position. If such a case does not exist, remove the last occurrence of the digit. The algorithm runs in O(n) time and O(1) space.

Is Remove Digit From Number to Maximize Result asked at Google/Amazon/Meta?

Problems involving greedy digit manipulation and string-based number optimization appear frequently in interviews at companies like Amazon, Google, and Meta. Variants include removing digits to maximize or minimize a number and monotonic stack style greedy decisions.

What data structure is used in Remove Digit From Number to Maximize Result?

The problem mainly uses string traversal and greedy decision making. No complex data structures are required. The solution simply iterates through the string and constructs the resulting string after removing the selected digit.

What is the time complexity of Remove Digit From Number to Maximize Result?

The optimal greedy solution runs in O(n) time because the string is scanned once to find the best digit to remove. Space complexity is O(1) if the result is constructed directly from the original string. A brute force enumeration approach would take O(n²) time since it generates and compares multiple candidate strings.

Description Hints 3 Solution Video 5:57

2259. Remove Digit From Number to Maximize Result

Easy48.4% acceptance6 companies

You are given a string number representing a positive integer and a character digit.

Return the resulting string after removing exactly one occurrence of digit from number such that the value of the resulting string in decimal form is maximized. The test cases are generated such that digit occurs at least once in number.

Example 1:

Input: number = "123", digit = "3"
Output: "12"
Explanation: There is only one '3' in "123". After removing '3', the result is "12".

Example 2:

Input: number = "1231", digit = "1"
Output: "231"
Explanation: We can remove the first '1' to get "231" or remove the second '1' to get "123".
Since 231 > 123, we return "231".

Example 3:

Input: number = "551", digit = "5"
Output: "51"
Explanation: We can remove either the first or second '5' from "551".
Both result in the string "51".

Constraints:

2 <= number.length <= 100
number consists of digits from '1' to '9'.
digit is a digit from '1' to '9'.
digit occurs at least once in number.

Asked at 6 companies

Infosys Microsoft

Google Amazon Meta Bloomberg

Topics

Hints open one at a time

Hint 1

The maximum length of number is really small.

Hint 2

Iterate through the digits of number and every time we see digit, try removing it.

Hint 3

To remove a character at index i, concatenate the substring from index 0 to i - 1 and the substring from index i + 1 to number.length - 1.

5:57

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