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.util.*;
public class Test {
	
	boolean check(int x)
	{
		while(x!=0)
		{
			int y = x%10;
			if(y==7)
				return true;
			x/=10;
		}
		return false;
	}
	
	void solve()
	{
		Scanner sc = new Scanner(System.in);
		int x = sc.nextInt();
		int h = sc.nextInt();
		int m = sc.nextInt();
		
		int t = 0;
		while(true)
		{
			if(check(h) || check(m))
				break;
			
			//System.out.println(h+" : "+m);
			
			t++;
			if(m-x>=0)
			{
				m-=x;
			}
			else
			{
				if(h-1>=0)
					h--;
				else
				{
					h--;
					h+=24;
				}
				m-=x;
				m+=60;
			}
			
		}
		
		System.out.println(t);
		
	}

	public static void main(String[] args) {
		new Test().solve();

	}

}
