Coin Change II
DP on Subsequences DSA practice problem on Onlearn.
Difficulty: hard.
Topics: Number of ways to make a coin change (Coin Change 2 problem), Dynamic Programming, Memoization, Tabulation, Space Optimization, Recursion, Arrays, Time Complexity, Space Complexity, Subset Sum, Edge Cases, dynamic programming, memoization, tabulation, space optimization, recursion.
Problem: Ways to Make a Coin Change Problem Statement You are given an array Arr with N distinct coin denominations and a target sum T. You have an infinite supply of each coin denomination. Your task is to find the total number of distinct ways you can sum up the coin values to achieve the target sum T. Input Specification The first line contains an integer N, the number of coin denominations. The second line contains N space separated integers, representing the coin denominations Arr[0], Arr[1], ..., Arr[N 1]. The third line contains an integer T, the target sum. Output Specification Print a single integer, the total number of ways to make the target sum. Constraints 1 <= N <= 100 1 <= Arr[i] <= 1000 1 <= T <= 1000 Sample Test Case Input: Output: Explanation: The ways to make a sum of 4 using coins {1, 2, 3} are: 1. (1, 1, 1, 1) 2. (1, 1, 2) 3. (1, 3) 4. (2, 2) Difficulty Level Medium