Question

Implement the squeeze() method in the provided ArraySqueeze class so that it performs as indicated in the comment. The main() method in this class runs some test cases on squeeze(). You should also add a few nontrivial and interesting test cases of your own at the end of main().

package A1;

/**
 * The purpose of this class is to squeeze an array of ints.
 * 
 * The main method runs some tests.
 * 
 * @author andy
 * 
 */

public class ArraySqueeze {

        /**
         * squeeze() takes an array of ints. On completion the array contains the
         * same numbers, but wherever the array had two or more consecutive
         * duplicate numbers, they are replaced by one copy of the number. Hence,
         * after squeeze() is done, no two consecutive numbers in the array are the
         * same.
         * 
         * Any unused elements at the end of the array are set to -1.
         * 
         * For example, if the input array is [ 4 , 1 , 1 , 3 , 3 , 3 , 1 , 1 ], it
         * reads [ 4 , 1 , 3 , 1 , -1 , -1 , -1 , -1 ] after squeeze() completes.
         * 
         * @param ints
         *            the input array.
         */

        public static void squeeze(int[] ints) {

                // TODO: Fill in your solution here. Ours takes linear time and is less than 10 lines long,
                // not counting blank/comment lines or lines already present in this file.

        }

  

        /**
         * main() runs test cases on your squeeze() method. Prints summary
         * information on basic operations and halts with an error (and a stack
         * trace) if any of the tests fail.
         */

        public static void main(String[] args) {
                String result;

                System.out.println("Let's squeeze arrays!\n");

                int[] test1 = {3, 7, 7, 7, 4, 5, 5, 2, 0, 8, 8, 8, 8, 5};
                System.out.println("squeezing " + TestHelper.stringInts(test1) + ":");
                squeeze(test1);
                result = TestHelper.stringInts(test1);
                System.out.println(result + "\n");
                TestHelper.verify(result.equals(
                  "[ 3 , 7 , 4 , 5 , 2 , 0 , 8 , 5 , -1 , -1 , -1 , -1 , -1 , -1 ]"),
                                                "BAD SQEEZE!!!  No cookie.");

                int[] test2 = {6, 6, 6, 6, 6, 3, 6, 3, 6, 3, 3, 3, 3, 3, 3};
                System.out.println("squeezing " + TestHelper.stringInts(test2) + ":");
                squeeze(test2);
                result = TestHelper.stringInts(test2);
                System.out.println(result + "\n");
                TestHelper.verify(result.equals(
                   "[ 6 , 3 , 6 , 3 , 6 , 3 , -1 , -1 , -1 , -1 , -1 , -1 , -1 , -1 , -1 ]"),
                                                "BAD SQEEZE!!!  No cookie.");

                int[] test3 = {4, 4, 4, 4, 4};
                System.out.println("squeezing " + TestHelper.stringInts(test3) + ":");
                squeeze(test3);
                result = TestHelper.stringInts(test3);
                System.out.println(result + "\n");
                TestHelper.verify(result.equals("[ 4 , -1 , -1 , -1 , -1 ]"),
                                "BAD SQEEZE!!!  No cookie.");

                int[] test4 = {0, 1, 2, 3, 4, 5, 6};
                System.out.println("squeezing " + TestHelper.stringInts(test4) + ":");
                squeeze(test4);
                result = TestHelper.stringInts(test4);
                System.out.println(result + "\n");
                TestHelper.verify(result.equals("[ 0 , 1 , 2 , 3 , 4 , 5 , 6 ]"),
                                "BAD SQEEZE!!!  No cookie.");

                System.out.println("\nAdditional tests done by the student or TA:\n");

                // Insert your additional test cases here.
        }
}

Answer 1

This solution take linear time.

public static void squeeze(int[] ints) {

  

int c=0, i = 0, p;

int arr[] = new int[ints.length];

for(i=0; i<ints.length-1; ++i)

   p = (ints[i] == ints[i+1]) ? arr[i+1] = -1 : -1;

for(i=0; i<arr.length; ++i)

p = (arr[i] != -1) ? ints[c++] = ints[i] : -1;

for(i=c; i<ints.length; ++i)

ints[c++] = -1;

}

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SEE OUTPUT

52 33 340 35 public static void squeeze(int[] ints) { 36 // TODO: Fill in your solution here. Ours takes linear time and is less than 10 lines long, 37 38 int c=0, i = 0, p; int arr[] = new int[ints.length]; for(i=0; i<ints.length-1; ++i) p = (ints [i] == ints [i+1]) ? arr[i+1] = -1 : -1; for(i=0; i<arr.length; ++i) p = (arr[i] != -1) ? ints [C++] = ints[i] : -1; for(i=c; i<ints.length; ++i) ints[/c++] = -1; 4 49 50 51 132 Problems @ Javadoc e Declaration Search Console X <terminated> Array Squeeze (Java Application] /Library/Java/JavaVirtual Machines/jdk1.8.0_231.jdk/Contents/Home/bin/java (Jan 26, 2020, 11:47:18 PM) Let's squeeze arrays! -1] |[3, 7, 4, 5, 2, 0, 8, 5, -1, -1, -1, -1, -1, -1] , 3, 6, 3, 6, 3, -1, -1, -1, -1, -1, -1, -1, -1, [4, -1, -1, -1, -1] | [0, 1, 2, 3, 4, 5, 6] Additional tests done by the student or TA:

PLEASE COMMENT if there is any concern.

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