// Program to test solutions to problem #7 on the cse142 final, spring 2015.
// Fill in your solution to expand, then compile and run the program.

import java.util.*;

public class FinalTest7 {
    public static int[] expand(int[] data) {
        // fill in your solution here
        // you can also rename the parameter above
    }

    // this is the sample solution
    public static int[] expand2(int[] data) {
        int len = 0;
        for (int i = 0; i < data.length / 2; i++) {
            len = len + data[2 * i];
        }
        int[] result = new int[len];
        int index = 0;
        for (int i = 0; i < data.length / 2; i++) {
            int times = data[2 * i];
            int n = data[2 * i + 1];
            for (int j = 0; j < times; j++) {
                result[index] = n;
                index++;
            }
        }
        return result;
    }

    private static int testCount, failCount;

    public static final int ERRORS_MAX = 15;

    public static void main(String[] args) {
        failCount = 0;
        test(new int[] {3, 8, 4, 2, 5, 1});
        test(new int[] {2, 5, 6, 2, 0, 9, 8, 7});
        test(new int[] {0, 14, 4, 2, 3, -8, 4, -2, 1, -1, 1, 1, 6, 8, 7, 7});

        if (failCount == 0) {
            System.out.println("PASSED all " + testCount + " tests");
        } else {
            System.out.println("failed " + failCount + " of " + testCount +
                               " tests");
        }
    }

    public static void test(int[] allData) {
        for (int i = 0; i <= allData.length / 2; i++) {
            testCount++;
            int[] data = Arrays.copyOf(allData, 2 * i);
            int[] copy = Arrays.copyOf(allData, 2 * i);
            int[] result2 = expand2(data);
            int[] result1 = null;
            boolean fail = false;
            RuntimeException except = null;
            try {
                result1 = expand(data);
            } catch (RuntimeException e) {
                fail = true;
                except = e;
            }
            fail = fail || !Arrays.equals(result1, result2) || 
                !Arrays.equals(data, copy);
            
            if (fail) {
                System.out.println("testing expand(" + Arrays.toString(copy)
                                   + ")");
                if (except != null) {
                    StackTraceElement[] trace = except.getStackTrace();
                    int line = trace[0].getLineNumber();
                    System.out.println("Threw exception at line#" + line);
                } else {
                    if (!Arrays.equals(result1, result2)) {
                        System.out.println("correct: " + 
                                           Arrays.toString(result2));
                        System.out.println("yours  : " + 
                                           Arrays.toString(result1));
                    }
                    if (!Arrays.equals(data, copy)) {
                        System.out.println("data was: " + 
                                           Arrays.toString(copy));
                        System.out.println("data now: " + 
                                           Arrays.toString(data));
                    }
                }
                System.out.println();
                failCount++;
                if (failCount > ERRORS_MAX) {
                    System.out.println("exceeds " + ERRORS_MAX + " errors");
                    System.out.println("with " + (testCount - failCount) +
                                       " correct");
                    System.exit(0);
                }
            }
        }
    }
}