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.InputStream;
import java.io.InputStreamReader;
import java.util.StringTokenizer;

public class cntst {
	static int h,m;
	public static void main(String[] args) throws IOException {
		Scanner sc=new Scanner(System.in);
		int x=sc.nextInt();
		h=sc.nextInt();
		m=sc.nextInt();
		String s=""+m+h;
		for(int i=0;i<s.length();++i)
			if(s.charAt(i)=='7')
			{
				System.out.println(0);return;
			}
		int cnt=1;
		while(!sub(x))
			cnt++;
		System.out.println(cnt);
	}
	public static boolean sub(int x) {
		if(x>m)
		{	m+=(60-x);
			h--;
			if(h<0)
				h=23;
		}
		else
			m-=x;
		String s=""+m+h;
		for(int i=0;i<s.length();++i)
			if(s.charAt(i)=='7')
				return true;
		return false;
		}
	
	static class Scanner 
	{
		StringTokenizer st;
		BufferedReader br;
 
		public Scanner(InputStream s){	br = new BufferedReader(new InputStreamReader(s));}
 
		public String next() throws IOException 
		{
			while (st == null || !st.hasMoreTokens()) 
				st = new StringTokenizer(br.readLine());
			return st.nextToken();
		}
 
		public int nextInt() throws IOException {return Integer.parseInt(next());}
 
		public long nextLong() throws IOException {return Long.parseLong(next());}
 
		public String nextLine() throws IOException {return br.readLine();}
 
		public double nextDouble() throws IOException
		{
			String x = next();
			StringBuilder sb = new StringBuilder("0");
			double res = 0, f = 1;
			boolean dec = false, neg = false;
			int start = 0;
			if(x.charAt(0) == '-')
			{
				neg = true;
				start++;
			}
			for(int i = start; i < x.length(); i++)
				if(x.charAt(i) == '.')
				{
					res = Long.parseLong(sb.toString());
					sb = new StringBuilder("0");
					dec = true;
				}
				else
				{
					sb.append(x.charAt(i));
					if(dec)
						f *= 10;
				}
			res += Long.parseLong(sb.toString()) / f;
			return res * (neg?-1:1);
		}
 
		public boolean ready() throws IOException {return br.ready();}
 
 
	}
}
