// Report on animal birth weights as entered by user
// Do not change your growth program to use this reading approach
// Beth Katz - April 2009

import java.util.Scanner;

public class BirthWeightInt {
	public static final int MaxInput = 20;

	public static void main(String[] args) {
		Scanner input = new Scanner(System.in);

		System.out.println("Enter up to " + MaxInput + " integer values on a line.");
		Scanner line = new Scanner(input.nextLine( )); // build Scanner with input line
		int[ ] weights = read(line);                   // fill array from that Scanner
		print(weights);
		
		System.out.println("Let's look for values in that line you just typed.");
		System.out.println("Enter value to count: ");
		while (input.hasNextInt( )) {
			int target = input.nextInt( );
			int answer = countOccurances(weights, target);
			System.out.println(target + " occurs " + answer + " times");
			System.out.println("Enter value to count or type control-d to stop");
		}
		System.out.println("Program finished.");
	}

	// read many values from a Scanner and copy them into an array
	// just big enough to hold them
	// returns array holding up to MaxInput values
	// see p. 393 of text
	public static int[ ] read(Scanner in) {
		int count = 0;
		int[ ] original = new int[MaxInput];

		while (count < MaxInput && in.hasNextInt( )) {
			original[count] = in.nextInt( );
			count++;
		}

		return rightSizeArray(original, count);
	}

	// copy the first 'used' values from original into right-sized array
	public static int[ ] rightSizeArray(int[ ] original, int used) {
		int[ ] copy = new int[used];		
		for (int i = 0; i < used; i++) {
			copy[i] = original[i];
		}
		return copy;
	}

	// print array all on one per line with indexes
	public static void print(int[ ] a) {
		for (int i = 0; i < a.length; i++) {
			System.out.print("[" + i + "] " + a[i] + " ");
		}
		System.out.println( );
	}

	// returns how many times target value appears in array
	public static int countOccurances(int[ ] a, int target) {
		int count = 0;
		for (int i = 0; i < a.length; i++) {
			if ( a[i] == target) {
				count++;
			}
		}
		return count;
	}
}