Midterm Ans

Q1) 2pts each for a), b), c),f). 3pts each for d) e)
WhileTest

2
1

ForTest

00000
2222
444

StringTest

1: 10
2: i
3: 3
4: -1

StaticTest

1: 6
2: 9
3: 7
4: 11
5: 5
6: ab

Sub/Super

1: 2, 4, 2, 2, 2
2: 10, 11, 0, 1, 0
3: 11, 13, 1, 1, 1

Test

1: 4.4
2: 5.5
3: 4.4
4: 5.5

Q2)
1 pt for each mistake found, 1 pt for correction.
Error1
a)

public class Error1 {
    public void method(int a) {
        a = 3;
        return;
    }
    
    public void method() {
        System.out.println("Hi");
        return;
    }
    
    public double method2() {
        return 3.5/2;
    }
    
    public double method2(int a) {
        return a++;
    }    
}

public class Error2 {
    public static void main(String[] args) {
        int a=1;
        if(a==1) {
            System.out.println("a is 1");
        } else {
            System.out.println("a is not 1");
        }
        
        float f = 2.3f;
        if(f > 2.1) {
            System.out.println("f is greater than 2.1");
        }
    }
}

public class abstract ClassB extends ClassA {
    public int method(int a) {
        return 2*a;
    }
    
    public int method(int a, int b) {
        return a + b;
    }
}

Q3)

a) 3,4,5,6

b)1,4

Q4)

public class IntArray {
    int[] cut(int[] array, int max) {
        int num = 0;
        // 4pts
        for(int i = 0; i < array.length; i++) {
            if(array[i] <= max) {
                num++;
            }
        }
        int[] result = new int[num]; // 1pt
        int j = 0;
       // 5pts
        for(int i = 0; i <= result.length; i++) {
            if(array[i] <= max) {
                result[j] = array[i];
                j++;
            }
        }
        return result; //1pt
    }
}

Q5

public class CountABC {
    public static int count(String s) {
        int count = 0;
        int start = 0;
        String find = "ABC";
        while(s.indexOf(find, start) != -1) {
            start = s.indexOf(find, start) + 1;
            count++;
        }
        return count;
    }
            
    public static void main(String[] args) {
        String s = "abcABCdefABC123456ABC###ABC%%%";
        System.out.println(count(s));
    }
}