// Arup Guha
// 7/13/2014
// Solution to 2006 UCF HS Contest Problem: Ali's Short Bus

import java.util.*;
import java.io.*;

public class bus {

	public static void main(String[] args) throws Exception {

		Scanner stdin = new Scanner(new File("bus.in"));
		int[] data = new int[5];
		for (int i=0; i<5; i++)
			data[i] = stdin.nextInt();
		int loop = 1;

		// Go through each case.
		while (!zero(data)) {

			// Desired slope.
			double slope = (double)(data[0]-data[2])/(data[3]-data[1]);

			// Our result.
			double speed = Math.max(0, (data[0] - data[4])/slope + data[1]);

			// Print - watch out for rounding...
			System.out.printf("Ali's Bus Trip #%d: The bus must travel at least %d kph.\n", loop, (int)(Math.ceil(speed)));

			// Get next case.
			for (int i=0; i<5; i++)
				data[i] = stdin.nextInt();
			loop++;
		}

		stdin.close();
	}

	// Returns true iff arr is all zero.
	public static boolean zero(int[] arr) {
		for (int i=0; i<arr.length; i++)
			if (arr[i] != 0)
				return false;
		return true;
	}
}