Questions tagged [coin-change]
The coin-change tag has no usage guidance.
28 questions
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Minimum coins to make change when real numbers are allowed
There is the classical version of the minimum coins to make change problem where the change and the set of coins available are all integers. Given an infinite amount of each type of coin, we're asked ...
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1
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Coin exchange, find different triples of values
Suppose i have 3 coins: A, B, C. Each one of them have different value: a, b, c. And if want to exchange coins A for coins B, i need to be able to give exactly a units of currency A and get exactly b ...
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What is the best way to solve the coin change problem using dynamic programming?
I have found two ways of applying dynamic programming to the coin change problem of finding the minimum number of coins from a given set of denominations to make a given sum. I wanted to know if one ...
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Why does the order of the nested loops matter when solving the Coin Change problem?
The Coin Change problem is stated as:
Given an integer array coins[ ] of size N representing different
denominations of currency and an integer sum, find the number of ways
you can make sum by using ...
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1
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1
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Unable to understand how the while loop extracts the least number of coins with given sum
I was reading this classical Coin Problem (7.1): Given a set
of coin values coins = {c1, c2,..., ck} and a target sum of money n, our task is to
form the sum n using as few coins as possible.
I fully ...
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1
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122
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Can the algorithm be optimized?
I am new to backtracking and recursion. I have seen numerous explanations on how on to find the minimum number of coins needed to make a particular amount. This involves a top down dynamic approach ...
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1
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3k
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Min-coin change problem with limited coins
I have been assigned the min-coin change problem for homework. I have to calculate the least number of coins needed to make change for a certain amount of cents in 2 scenarios: we have an infinite ...
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2
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3
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530
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Algorithm for fewest number of moves with artificial minimum
I asked a question recently, but I need to be able to add an artificial minimum number of steps that can be larger than the Dijkstra minimum.
To summarize, I built an undirected graph with edges ...
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dynamic pseudo-code for simplified coin changing algorithm
As a homework exercise our professor presented to us a simplified version of the coin-changing problem in which we do not need to minimize the number of coins used or track the number of possible ...
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What Are the Ideas Behind Variations of the Coin Change Problem?
Problem: given a set of n coins of unique face values, and a value
change, find number of ways of making change for ...
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3k
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DP recurrence relations: Coin change vs Knapsack
Take:
KP recurrence relation
$ max { [v + f(k-1,g-w ), f(k-1,g)] } $ if w <= g and k>0
CCP recurrence relation
$ min {[1 + f(r,c-v), f(r-1,c)]} $ if v <= c and r>0
I don't ...
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"Ways to make change for a dollar": How to optimize with constraints
I'm working on an algorithm that takes a number of unit coins ([1, 2, 5, 10] for example) and a certain amount of money (13 in this case), and figures out how many ways there are to provide change for ...
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Solving "coin exchange" for coins of power values by greedy algorithm
When solving the problem of coin exchange by greedy algorithm, why will we will always have the correct result if the coin values are $1, a, a^2, \cdots, a^n$, where $a\ge 2$ and $n\gt 0$?
For ...
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Coin Change Problem Recurrence Relation with one parameter
I have been looking through the recursive formulation for the coin change problem here and am wondering if it is possible to define the function $ C(N, m) $ in one parameter as $C(N)$, therefore not ...
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Reducing Coin Change Problem running time to depend on the denominations, not sum being changed
I asked my Advanced Algorithms professor recently if we could solve the coin change problem (least number of coins necessary to make change for S cents using denominations d1, d2, ... dk). I thought ...
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Space complexity of Coin change with memoization
I've read conflicting answers for the space complexity of the top down implementation w/ memoization for the classic coin change problem. Would this be O(N * M) space as Interview Cake says https://...
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Find the lexicographically smallest order of N numbers such that the total of N numbers <= Threshold value
GIven a number N, Threshold T and an array A. Find the lexicographically smallest order of N numbers from A such that the total of these N numbers is <= T.
This question is a simplification of ...
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Is this solution is bad for the coin change problem? [closed]
was doing coin change problem as an assignment(didnt know before), after came with this solution i checked the solutions available couldnt find a similar one like this, just curious.
removing the ...
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Does an algorithm exist for solving the change-making problem using a finite coin library of known size?
I'm currently working on implementing an algorithm to solve a real-world problem I'm encountering in a lab, but with little background in algorithms, I'm struggling to create an ideal solution.
I ...
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Printing actual solutions for the coin exchange problem
As I teach myself dynamic programming, I have learned about the coin exchange problems. Specially this site: https://www.geeksforgeeks.org/dynamic-programming-set-7-coin-change/ provides great insight ...
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Dynamic Programming for a variant of the coin exchange problem
I am interested in solving a variant of the coin exchange problem. Recall the formal definition of the coin exchange problem:
Given a value N, if we want to make change for N cents, and we have ...
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Implementing supplies in Coin change problem
I started an algorithm course in C two months ago, for the last weeks I've been trying to solve this problem , i ran out of time but I cannot find an acceptable solution. Basically It's a coin change ...
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Analyzing time complexity for change making algorithm (Brute force)
I'm new to analyzing time complexities and I have a question. To compute the nth fibonacci number, the recurrence tree will look like so:
Since the tree can have a maximum height of 'n' and at every ...
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Can counting problems have optimal substructure?
I understand that for a problem to be solvable using dynamic programming, it needs to have the following properties:
optimal substructure
overlapping subproblems
I stumbled upon an article which ...
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Recurrence relation of the coin change problem
I'm trying to wrap my head around the coin change problem, where you try to find the total number of ways $N$ cents can be exchanged using $M$ coins $\{C_1, C_2, ..., C_m\}$.
The recurrence relation ...
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What are applications of Coin Change problem?
I've read so many about the Coin Change problem, debates about wheather it is solvable using Greedy, Dynamic Programming and so on.
Nevertheless I cannot find an application of this problem.
What ...
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Coin Change Problem(Greedy Algorithm)
In Coin Change Problem, if the ratio of Coin Value ($\frac{Coin_(i+1)}{coin(i)}$) is always increasing then we can use Greedy Algorithm?
Example- $(1,3,4)$ are denominations of coin.
If I want to pay ...
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1
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A variant of coin change problem
Consider a cashier machine that takes payments in coins. We feed the machine coins one by one until the value is more than the amount we should have paid. Then the machine returns the extra amount in ...
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