digit-DP

38 posts

Last Updated: 01 August 2026

Given two integers n and k, find the nth non-negative integer whose binary representation contains at most k set bits (1s). The numbers are considered in increasing order ...read more

DSA

Binary Search

digit-DP

Count Valid Numbers with Equal Digit Frequencies

Last Updated: 23 July 2025

Given an integer n (1 = n = 1010), count the number of valid numbers in the range [1, n] (inclusive).Note: A number is called valid if digits 2, 4, and 8 occur in it with ...read more

Geeks Premier League 2023

Count of non-consecutive Ones in Binary range

Last Updated: 23 July 2025

Given two positive integers 'L' and 'R', the task is to return the number of the integers in the range[L, R] inclusive,whose binary representationsdo notcontain consecutiv...read more

Dynamic Programming

Advanced Data Structure

DSA

digit-DP

Count of N digit numbers which contains all single digit primes

Last Updated: 23 July 2025

Given a positive integer n, the task is to count the number of n digits numbers which contain all single digit primes.Examples:Input: n = 4Output: 24Explanation: The numbe...read more

Count of N-digit numbers with at least one digit repeating

Last Updated: 23 July 2025

Given a positive integer n, the task is to find the count of n-digit numbers with at least one repeated digit.Examples:Input: n = 2Output: 9Explanation: All the 2-digit nu...read more

Count of N-digit numbers having each digit as the mean of its adjacent digits

Last Updated: 23 July 2025

Given a positive integer N, the task is to count the number of N-digit numbers where each digit in the number is the mean of its two adjacent digits.Examples :Input: N = 1...read more

Count of N-digit numbers whose bitwise AND of adjacent digits equals 0

Last Updated: 23 July 2025

Given a positive integer N, the task is to count the number of N-digit numbers such that the bitwise AND of adjacent digits equals 0.Examples:Input: N = 1Output: 10Explana...read more

Count possible decoding of a given digit sequence with hidden characters

Last Updated: 23 July 2025

Given a string S containing digits and character '*' i.e. hidden character, the task is to find the number of ways to decode this hidden character of the given string.Sinc...read more

interview-preparation

digit-DP

Total count of sorted numbers upto N digits in range [L, R] (Magnificent necklace combinatorics problem)

Last Updated: 03 October 2025

Given three integers N, L, and R, the task is to print the total count of ways to form a necklace of at most N pearls such that the values of a pearl lie in the range [L, ...read more

Permutation and Combination

digit-DP

Count numbers in a given range having prime and non-prime digits at prime and non-prime positions respectively

Last Updated: 23 July 2025

Given two integers L and R, the task is to find the count of numbers in the range [L, R] having prime digits at prime positions and non-prime digits at non-prime positions...read more

Count possible N-digit numbers such that each digit does not appear more than given number of times consecutively

Last Updated: 23 July 2025

Given an integer N and an array maxDigit[], the task is to count all the distinct N-digit numbers such that digit i does not appear more than maxDigit[i] times. Since the ...read more

Technical Scripter 2020

DSA

Memoization

digit-DP

Count numbers from a given range whose product of digits is K

Last Updated: 03 October 2025

Given three positive integers L, R and K, the task is to count the numbers in the range [L, R] whose product of digits is equal to KExamples:Input: L = 1, R = 130, K = 14O...read more

DSA

number-digits

digit-DP

Count of numbers from range [L, R] whose sum of digits is Y | Set 2

Last Updated: 03 October 2025

Given three positive integers L, R and Y, the task is to count the numbers in the range [L, R] whose sum of digits is equal to YExamples:Input: L = 500, R = 1000, Y = 6Out...read more

DSA

number-digits

digit-DP

Minimum removals required such that sum of remaining array modulo M is X

Last Updated: 23 July 2025

Given an array arr[] consisting of N positive integers and the integers X and M, where 0 = X M, the task is to find the minimum number of elements required to be removed ...read more

Count numbers in range [L, R] having K consecutive set bits

Last Updated: 23 July 2025

Given three positive integers l, r, and k, the task is to find the count of numbers in the range [l, r] having k consecutive set bits in their binary representation.Exampl...read more

binary-representation

digit-DP

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