problem

JOI, who has been suffering from his winter vacation homework every time, decided to do his homework systematically this time. Homework is a national language and math drill, with a national language drill on page A and a math drill on page B.

JOI can advance the Japanese drill up to C pages and the math drill up to D pages a day, but if he does his homework, he can't play that day.

There are L days during the winter vacation, and JOI must finish his homework during the winter vacation. Create a program that asks how many days JOI can play during the winter vacation.



input

The input consists of 5 lines, with one positive integer written on each line.

The integer L (2 ≤ L ≤ 40) is written on the first line, which indicates the number of days of winter vacation.

The integer A (1 ≤ A ≤ 1000) is written on the second line, which indicates the number of pages of the Japanese drill.

The integer B (1 ≤ B ≤ 1000) is written on the third line, which indicates the number of pages of the math drill.

The integer C (1 ≤ C ≤ 100) is written on the 4th line, which indicates the maximum number of pages of a national language drill that JOI can advance in a day.

The integer D (1 ≤ D ≤ 100) is written on the 5th line, which indicates the maximum number of pages of the math drill that JOI can advance in a day.

However, given the input data, JOI is guaranteed to be able to finish his homework during the winter vacation and play for at least a day.

Example

Input

20
25
30
6
8


Output

15
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;


public class Main {

	public static void main(String[] args) {
		Main main = new Main();
		main.playDaysCalculation();
		return;
	}
	
	//遊べる日数を計算する
	private void playDaysCalculation() {
		
		BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in)); //標準入力
		
		try {
			
			String inputStr = bufferedReader.readLine();
			int winterBreakDays = Integer.parseInt(inputStr);
			
			String inputStr2 = bufferedReader.readLine();
			double languageWorkbookPageNum = Double.parseDouble(inputStr2);
			
			String inputStr3 = bufferedReader.readLine();
			double arithmeticWorkbookPageNum = Double.parseDouble(inputStr3);
			
			String inputStr4 = bufferedReader.readLine();
			double languageProgressNum = Double.parseDouble(inputStr4);
			
			String inputStr5 = bufferedReader.readLine();
			double arithmeticProgressNum = Double.parseDouble(inputStr5);
			
			double languageWorkbookEndDays = languageWorkbookPageNum / languageProgressNum;
			double arithmeticWorkbookEndDays = arithmeticWorkbookPageNum / arithmeticProgressNum;
			
			int workbookEndDays = 0;
			if (languageWorkbookEndDays > arithmeticWorkbookEndDays) {
				workbookEndDays = (int)Math.ceil(languageWorkbookEndDays);
			} else if (languageWorkbookEndDays < arithmeticWorkbookEndDays) {
				workbookEndDays = (int)Math.ceil(arithmeticWorkbookEndDays);
			} else if (languageWorkbookEndDays == arithmeticWorkbookEndDays) {
				workbookEndDays = (int)Math.ceil(languageWorkbookEndDays);
			}
			
			System.out.println(winterBreakDays - workbookEndDays);
			
		} catch (IOException e) {
			// TODO 自動生成された catch ブロック
			e.printStackTrace();
		}
		
	}

}