// Program to test solutions to problem #10 on the cse142 final, autumn 2014.
// Fill in your solution to removeZeros, then compile and run the program.

import java.util.*;

public class FinalTest10 {
    public static void removeZeros(int[] list) {
        // fill in your solution here
        // you can also rename the parameter above
    }

    // this is the sample solution
    public static void removeZeros2(int[] list) {
        int numNonZero = 0;
        for (int i = 0; i < list.length; i++) {
            if (list[i] != 0) {
                list[numNonZero] = list[i];
                numNonZero++;
            }
        }
        for (int i = numNonZero; i < list.length; i++) {
            list[i] = 0;
        }
    }

    private static int count, failCount;
    private static Random r;

    public static final int ERRORS_MAX = 10;

    public static void main(String[] args) {
        failCount = 0;
        r = new Random();
        for (int i = 0; i <= 15; i++) {
            test(i);
        }
        if (failCount == 0) {
            System.out.println("PASSED all " + count + " tests");
        }
    }

    public static void test(int i) {
        int[] data = new int[i];
        test(data, 0);
    }
    
    public static void test(int[] data, int index) {
        if (index == data.length) {
            count++;
            int[] data1 = Arrays.copyOf(data, data.length);
            int[] data2 = Arrays.copyOf(data, data.length);
            boolean fail = false;
            RuntimeException except = null;
            try {
                removeZeros(data1);
            } catch (RuntimeException e) {
                fail = true;
                except = e;
            }
            removeZeros2(data2);
            fail = fail || !Arrays.equals(data1, data2);
            if (fail) {
                if (except != null) {
                    StackTraceElement[] trace = except.getStackTrace();
                    int line = trace[0].getLineNumber();
                    System.out.println("FAIL with exception for " + 
                                       Arrays.toString(data) + " at line#"
                                       + line);
                } else {
                    System.out.println("FAIL for " + Arrays.toString(data));
                }
                System.out.println("Correct: " + Arrays.toString(data2));
                System.out.println("Theirs:  " + Arrays.toString(data1));
                System.out.println();
                failCount++;
                if (failCount > ERRORS_MAX) {
                    System.out.println("exceeds " + ERRORS_MAX + " errors");
                    System.out.println("with " + count + " correct");
                    System.exit(0);
                }
            }
        } else {
            data[index] = 0;
            test(data, index + 1);
            do {
                data[index] = r.nextInt(51) - 25;
            } while (data[index] == 0);
            test(data, index + 1);
        }
    }
}