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Problem: Find The K-th Lucky Number

Medium
30 min
Understand how to identify and generate the k-th lucky number, which consists only of digits 4 and 7, by applying bitwise manipulation techniques. This lesson helps you practice problem-solving skills relevant for coding interviews and teaches the logic behind efficient solution development.

Statement

A number is called lucky if it comprises only the digits 44 and 77. Your task is to return the k-th lucky number as a string for a given integer k

Constraints:

  • 1<=1 <= k <=109<= 10^9

Problem
Ask
Submissions

Problem: Find The K-th Lucky Number

Medium
30 min
Understand how to identify and generate the k-th lucky number, which consists only of digits 4 and 7, by applying bitwise manipulation techniques. This lesson helps you practice problem-solving skills relevant for coding interviews and teaches the logic behind efficient solution development.

Statement

A number is called lucky if it comprises only the digits 44 and 77. Your task is to return the k-th lucky number as a string for a given integer k

Constraints:

  • 1<=1 <= k <=109<= 10^9