Question

import java.util.Scanner;
import java.util.Arrays;

/*
You have 3 small methods to write for this exam;
public static int smallest(int[] v1, int[] v2)
public static int[] convert1(String str)
public static String convert2(int[] v)
  
The comments right before each of them tell you exactly what they are
expected to do. Read all requirements first, then start implementing
the easiest methods first. You may work on them in any order.

You are also provided with a main method and two other methods that
are just there to call the methods your wrote with a bunch of tests
and display the outcomes of these tests on the console to help you debug
them.

Please note that the tests we provide you with are not exhaustive.
Your methods still need to meet all requirements even if we did
not provide you with a test for that particular requirement.

if you want to add more tests, I recommend you modify the main method.
If you are comfortable with the code in the two testing methods,
you may also modify them instead but do not waste too much time working
on them.

Good luck!   
*/
public class COP2513E1{

/**
This method returns 1 if vector v1 is the "smallest", 2 if it is vector v2,
or 0 otherwise.
We define "smallest" as follows;
If one of the vector has fewer elements than the other, it is the smallest one.
If both are the same size, then we look at every element one by one in order.
As soon as one of the two vectors has an element that is < than the corresponding
element from the other vector, then it is recognized as the "smallest" one by our method.
**/
public static int smallest(int[] v1, int[] v2){
return 0; // always returns 0 for now, replace this with your code
}// end method smallest




/**
This method takes a string that is guaranteed to be made only
of digits, without spaces or anything else.
Examples; "123" or "0"
Your goal is to create a new array of int values that will hold
each of the digits specified in the String.
Example; if the string passed is "123" your returned array
should contain the int value 1 at index 0, the value 2 at index 1,
and the value 3 at index 2.
Once you are done, return the reference to your newly created
array of int values.
**/
public static int[] convert1(String str){
return new int[1]; // always returns an array with 1 element for now, replace this with your code
}// end method convert1


/**
This method does the opposite work of the above convert1 method.
It takes a vector of single-digit int values and return a string
with all these digits one after the other.
If one of the values in the vector is not in the range 0 to 9 inclusive,
then simply have this method return an empty string as result instead.
**/
public static String convert2(int[] v){
return ""; // always returns an empty string for now, replace this with your code
}// end method convert2



/*
Do not modify the main, or the other methods below this line,
except if you want to add more tests
*/
//=========================================================================


public static void main(String[] args){
testSmallest();
testConvert();
}// end main method
  
public static void testSmallest(){
System.out.println("Testing your method smallest(...)");
  
int[][] testVectors1 = {
{1,2,3},
{1,2,3,4},
{1,2,3},
{1,2,3},
{2,3,4}
};
  
int [][] testVectors2 = {
{1,2,3,4},
{1,2,3},
{1,2,3},
{2,3,4},
{1,2,3}   
};
  
int [] expectedOutcomes = {
1, 2, 0, 1, 2
};
  
if((expectedOutcomes.length != testVectors2.length)
||(expectedOutcomes.length != testVectors1.length)
||(testVectors1.length != testVectors2.length)){
System.out.println("All tables must have the same # of tests");
System.exit(-1);
}// end if
  
int nTests = expectedOutcomes.length;
  
for(int test=0; test < nTests ; test++){
int observedOutcome = smallest(testVectors1[test], testVectors2[test]);
System.out.print("\tTest #" + test + " with vectors "
+ Arrays.toString(testVectors1[test]) + " and " + Arrays.toString(testVectors2[test]));
if(observedOutcome == expectedOutcomes[test])
System.out.println(" SUCCEEDED");
else
System.out.println(" FAILED");
}// end for loop
} // end testSmallest method


public static void testConvert(){
String[] strings= {
"",
"0",
"9",
"12",
"123"
};
  
int[][] vectors = {
{},
{0},
{9},
{1,2},
{1,2,3}
};
  
System.out.println("\nTesting your method convert1(...)");
if(vectors.length != strings.length){
System.out.println("All tables must have the same # of tests");
System.exit(-1);
}// end if
  
for(int test=0 ; test < strings.length ; test++){
int[] observed = convert1(strings[test]);
System.out.print("\tTest #" + test + " with string \"" + strings[test] + "\"");
System.out.println(" "+ (Arrays.equals(observed, vectors[test])?"SUCCEEDED":"FAILED"));
}//end for loop
  
System.out.println("\nTesting your method convert2(...)");

for(int test=0 ; test < vectors.length ; test++){
String observed = convert2(vectors[test]);
System.out.print("\tTest #" + test + " with vector " + Arrays.toString(vectors[test]));
System.out.println(" "+ (observed.equals(strings[test])?"SUCCEEDED":"FAILED"));
}//end for loop

}// end testConvert method

} // end class

Answer 1

import java.util.Scanner;
import java.util.Arrays;

/*
You have 3 small methods to write for this exam;
public static int smallest(int[] v1, int[] v2)
public static int[] convert1(String str)
public static String convert2(int[] v)
  
The comments right before each of them tell you exactly what they are
expected to do. Read all requirements first, then start implementing
the easiest methods first. You may work on them in any order.

You are also provided with a main method and two other methods that
are just there to call the methods your wrote with a bunch of tests
and display the outcomes of these tests on the console to help you debug
them.

Please note that the tests we provide you with are not exhaustive.
Your methods still need to meet all requirements even if we did
not provide you with a test for that particular requirement.

if you want to add more tests, I recommend you modify the main method.
If you are comfortable with the code in the two testing methods,
you may also modify them instead but do not waste too much time working
on them.

Good luck!   
*/
public class COP2513E1 {

        /**
         * This method returns 1 if vector v1 is the "smallest", 2 if it is vector v2,
         * or 0 otherwise. We define "smallest" as follows; If one of the vector has
         * fewer elements than the other, it is the smallest one. If both are the same
         * size, then we look at every element one by one in order. As soon as one of
         * the two vectors has an element that is < than the corresponding element from
         * the other vector, then it is recognized as the "smallest" one by our method.
         **/
        public static int smallest(int[] v1, int[] v2) {
                
                if(v1.length < v2.length) {
                        return 1;
                } else if(v1.length > v2.length) {
                        return 2;
                } else {
                        
                        for(int i=0; i<v1.length; i++) {
                                
                                if(v1[i] < v2[i]) {
                                        return 1;
                                } else if(v1[i] > v2[i]) {
                                        return 2;
                                }
                                
                        }
                        
                }
                
                return 0; // always returns 0 for now, replace this with your code
        }// end method smallest

        /**
         * This method takes a string that is guaranteed to be made only of digits,
         * without spaces or anything else. Examples; "123" or "0" Your goal is to
         * create a new array of int values that will hold each of the digits specified
         * in the String. Example; if the string passed is "123" your returned array
         * should contain the int value 1 at index 0, the value 2 at index 1, and the
         * value 3 at index 2. Once you are done, return the reference to your newly
         * created array of int values.
         **/
        public static int[] convert1(String str) {
                
                int result[] = new int[str.length()];
                
                for(int i=0; i<str.length(); i++) {
                        result[i] = str.charAt(i) - '0';
                }
                
                return result; // always returns an array with 1 element for now, replace this with your code
        }// end method convert1

        /**
         * This method does the opposite work of the above convert1 method. It takes a
         * vector of single-digit int values and return a string with all these digits
         * one after the other. If one of the values in the vector is not in the range 0
         * to 9 inclusive, then simply have this method return an empty string as result
         * instead.
         **/
        public static String convert2(int[] v) {
                
                String s = "";
                for(int x: v) {
                        if(x < 0 || x > 9) {
                                return "";
                        }
                        s += x;
                }
                
                return s; // always returns an empty string for now, replace this with your code
        }// end method convert2

        /*
         * Do not modify the main, or the other methods below this line, except if you
         * want to add more tests
         */
//=========================================================================

        public static void main(String[] args) {
                testSmallest();
                testConvert();
        }// end main method

        public static void testSmallest() {
                System.out.println("Testing your method smallest(...)");

                int[][] testVectors1 = { { 1, 2, 3 }, { 1, 2, 3, 4 }, { 1, 2, 3 }, { 1, 2, 3 }, { 2, 3, 4 } };

                int[][] testVectors2 = { { 1, 2, 3, 4 }, { 1, 2, 3 }, { 1, 2, 3 }, { 2, 3, 4 }, { 1, 2, 3 } };

                int[] expectedOutcomes = { 1, 2, 0, 1, 2 };

                if ((expectedOutcomes.length != testVectors2.length) || (expectedOutcomes.length != testVectors1.length)
                                || (testVectors1.length != testVectors2.length)) {
                        System.out.println("All tables must have the same # of tests");
                        System.exit(-1);
                } // end if

                int nTests = expectedOutcomes.length;

                for (int test = 0; test < nTests; test++) {
                        int observedOutcome = smallest(testVectors1[test], testVectors2[test]);
                        System.out.print("\tTest #" + test + " with vectors " + Arrays.toString(testVectors1[test]) + " and "
                                        + Arrays.toString(testVectors2[test]));
                        if (observedOutcome == expectedOutcomes[test])
                                System.out.println(" SUCCEEDED");
                        else
                                System.out.println(" FAILED");
                } // end for loop
        } // end testSmallest method

        public static void testConvert() {
                String[] strings = { "", "0", "9", "12", "123" };

                int[][] vectors = { {}, { 0 }, { 9 }, { 1, 2 }, { 1, 2, 3 } };

                System.out.println("\nTesting your method convert1(...)");
                if (vectors.length != strings.length) {
                        System.out.println("All tables must have the same # of tests");
                        System.exit(-1);
                } // end if

                for (int test = 0; test < strings.length; test++) {
                        int[] observed = convert1(strings[test]);
                        System.out.print("\tTest #" + test + " with string \"" + strings[test] + "\"");
                        System.out.println(" " + (Arrays.equals(observed, vectors[test]) ? "SUCCEEDED" : "FAILED"));
                } // end for loop

                System.out.println("\nTesting your method convert2(...)");

                for (int test = 0; test < vectors.length; test++) {
                        String observed = convert2(vectors[test]);
                        System.out.print("\tTest #" + test + " with vector " + Arrays.toString(vectors[test]));
                        System.out.println(" " + (observed.equals(strings[test]) ? "SUCCEEDED" : "FAILED"));
                } // end for loop

        }// end testConvert method

} // end class

**************************************************

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