Jamie loves sleeping. One day, he decides that he needs to wake up at exactly hh: mm. However, he hates waking up, so he wants to make waking up less painful by setting the alarm at a lucky time. He will then press the snooze button every x minutes until hh: mm is reached, and only then he will wake up. He wants to know what is the smallest number of times he needs to press the snooze button.

A time is considered lucky if it contains a digit '7'. For example, 13: 07 and 17: 27 are lucky, while 00: 48 and 21: 34 are not lucky.

Note that it is not necessary that the time set for the alarm and the wake-up time are on the same day. It is guaranteed that there is a lucky time Jamie can set so that he can wake at hh: mm.

Formally, find the smallest possible non-negative integer y such that the time representation of the time x·y minutes before hh: mm contains the digit '7'.

Jamie uses 24-hours clock, so after 23: 59 comes 00: 00.

Input

The first line contains a single integer x (1 ≤ x ≤ 60).

The second line contains two two-digit integers, hh and mm (00 ≤ hh ≤ 23, 00 ≤ mm ≤ 59).

Output

Print the minimum number of times he needs to press the button.

Examples

Input

3
11 23


Output

2


Input

5
01 07


Output

0

Note

In the first sample, Jamie needs to wake up at 11:23. So, he can set his alarm at 11:17. He would press the snooze button when the alarm rings at 11:17 and at 11:20.

In the second sample, Jamie can set his alarm at exactly at 01:07 which is lucky.
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.math.BigInteger;
import java.util.Scanner;
import java.util.StringTokenizer;

public class A {
	
	public static void main(String args[]) {
		//Scanner in = new Scanner(System.in);
		input in = new input();
		int x = in.nextInt();
		String hh = in.next();
		String mm = in.next();
		int ans=0;
		while(!hh.contains("7") && !mm.contains("7")) {
			if(Integer.parseInt(mm)-x<0) {
				mm = String.valueOf(Integer.parseInt(mm)+60-x);
				if(hh.equals("00")) hh="24";
				hh = String.valueOf(Integer.parseInt(hh)-1);
				if(mm.length()<2) mm="0"+mm;
				if(hh.length()<2) hh="0"+hh;
			}
			
			else {
				mm = String.valueOf(Integer.parseInt(mm)-x);
				if(mm.length()<2) mm="0"+mm;
			}
			ans++;
		}
		System.out.println(ans);
	
	}

static class input{BufferedReader br;StringTokenizer st;public input(){
	br=new BufferedReader(new InputStreamReader(System.in));}String next(){while(st==null
	||!st.hasMoreElements()){try{st=new StringTokenizer(br.readLine());}catch(IOException e)
	{e.printStackTrace();}}return st.nextToken();}int nextInt(){return Integer.parseInt
	(next());}long nextLong(){return Long.parseLong(next());}double nextDouble(){return 
	Double.parseDouble(next());}String nextLine(){String str = "";try{str=br.readLine();}
	catch (IOException e){e.printStackTrace();}return str;}}

}