Making Change - Amazon Top Interview Questions


Problem Statement :


Find the minimum number of coins required to make n cents.

You can use standard American denominations, that is, 1¢, 5¢, 10¢, and 25¢.

Constraints

0 ≤ n < 2 ** 31

Example 1

Input

n = 3

Output

3

Explanation

You can make this with 3 pennies.

Example 2

Input

n = 5

Output

1

Explanation

You can make this with a 5 cent coin.

Example 3

Input

n = 6

Output

2

Explanation

You can make this with a 5 cent coin and a 1 cent coin.


Solution :



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                        Solution in C++ :

int solve(int n) {
    return (n / 25 + (n % 25) / 10 + ((n % 25) % 10) / 5 + (n % 5));
}
                    


                        Solution in Java :

import java.util.*;

class Solution {
    public int solve(int n) {
        int[] denominations = {25, 10, 5, 1};
        int cointCount = 0;
        for (int denomination : denominations) {
            if (n / denomination > 0) { // can take this coin
                cointCount += n / denomination;
                n = n % denomination;
            }
        }

        return cointCount;
    }
}
                    


                        Solution in Python : 
                            
class Solution:
    def solve(self, n):
        total = 0

        for coin in [25, 10, 5, 1]:
            this_coin = n // coin
            total += this_coin
            n -= coin * this_coin

            if n == 0:
                break

        return total


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