Problem:
Score : 300 points

Problem Statement

You've come to your favorite store Infinitesco to buy some ice tea.

The store sells ice tea in bottles of different volumes at different costs.
Specifically, a 0.25-liter bottle costs Q yen, a 0.5-liter bottle costs H yen, a 1-liter bottle costs S yen, and a 2-liter bottle costs D yen.
The store has an infinite supply of bottles of each type.

You want to buy exactly N liters of ice tea. How many yen do you have to spend?

Constraints

1 \leq Q, H, S, D \leq 10^8

1 \leq N \leq 10^9

All input values are integers.

Input

Input is given from Standard Input in the following format:

Q H S D
N

Output

Print the smallest number of yen you have to spend to buy exactly N liters of ice tea.

Sample Input 1

20 30 70 90
3

Sample Output 1

150

Buy one 2-liter bottle and two 0.5-liter bottles. You'll get 3 liters for 90 + 30 + 30 = 150 yen.

Sample Input 2

10000 1000 100 10
1

Sample Output 2

100

Even though a 2-liter bottle costs just 10 yen, you need only 1 liter.
Thus, you have to buy a 1-liter bottle for 100 yen.

Sample Input 3

10 100 1000 10000
1

Sample Output 3

40

Now it's better to buy four 0.25-liter bottles for 10 + 10 + 10 + 10 = 40 yen.

Sample Input 4

12345678 87654321 12345678 87654321
123456789

Sample Output 4

1524157763907942

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Wrong Answer)

import java.util.ArrayList;
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		
		String a = sc.next();
		
		ArrayList<String> r = new ArrayList<String>();
		r.add(a);
		
		for(int i = 0; i < a.length()-1; i++) {
			for(int j = i+1; j < a.length(); j++) {
				String str = reverse(a, i, j);
				if(!r.contains(str)) {
				r.add(str);
				}
				
			}
		}
		
		System.out.println(r.size());

	}
	
	static private String reverse(String str, int start, int end) {
		StringBuffer sb = new StringBuffer();
		for(int i = 0; i < start; i++) {
			sb.append(str.charAt(i));
		}
		
		for(int i = end; i >= start; i--) {
			sb.append(str.charAt(i));
		}
		
		for(int i = end + 1; i < str.length(); i++) {
			sb.append(str.charAt(i));
		}
		
		return sb.toString();
		
	}

}