Write a static method named hasMidpoint that accepts three integers as parameter

Question

Write a static method named hasMidpoint that accepts three integers as parameters and
returns true if one of the integers is the midpoint between the other two integers; that is, if
one integer is exactly halfway between them. Your method should return false if no such
midpoint relationship exists. The integers could be passed in any order; the midpoint
could be the 1st, 2nd, or 3rd. You must check all cases.

Calls such as the following should return true :
hasMidpoint(4, 6, 8)
hasMidpoint(2, 10, 6)
hasMidpoint(8, 8, 8)
hasMidpoint(25, 10, -5)

Calls such as the following should return false :
hasMidpoint(3, 1, 3)
hasMidpoint(1, 3, 1)
hasMidpoint(21, 9, 58)
hasMidpoint(2, 8, 16)

Explanation / Answer

public class MidPoint{
        public static boolean hasMidpoint(int a, int b ,int c ){
                int left,right,mid;
                int [] ar = new int[3]; // create a three element array
                ar[0] = a;ar[1]=b;ar[2]=c;   // put a, b ,c into it
                left = findMinInd(ar,3);        // find index of min element
                right = findMaxInd(ar,3);   // find index of largest element
                int thirdIndex = findThirdIndex(ar,left,right,3); //find index of remaining element
                mid =( ar[left] + ar[right] )/2;       // compute mid point
                System.out.println(left + ":" + thirdIndex + ":" + right);
                if ( ar[thirdIndex] == mid )      // if equal return true else return false
                        return true;
                else
                        return false;
        }
        static int findMinInd(int ar[],int size ){       // find index of min elem
                int min=999999;
                int ind = 0;
                for ( int i = 0 ;i<size;i++){
                        if (ar[i] < min ){
                                min = ar[i];
                                ind = i;
                        }
                }
                return ind;
        }
        static int findMaxInd(int ar[],int size ){        // find index of max eleme
                int max=-999999;
                int ind = 0;
                for ( int i = 0 ;i<size;i++){
                        if (ar[i] >= max ){
                                max = ar[i];
                                ind = i;
                        }
                }
                return ind;
        }
        public static void main(String args[]){
                System.out.println(hasMidpoint(4, 6, 8) );
                System.out.println(hasMidpoint(4, 3, 8) );
                System.out.println(hasMidpoint(1, 6, 8) );
                System.out.println(hasMidpoint(1, 3, 1) );
                System.out.println(hasMidpoint(3, 1, 3) );
                System.out.println(hasMidpoint(2, 10, 6) );
                System.out.println(hasMidpoint(8, 8, 8) );
                System.out.println(hasMidpoint(25, 10, -5) );

        }
        public static int findThirdIndex(int ar[],int left,int right,int size){ // find index of rem elem
                int ind = -1;
                for ( int i = 0;i < size;i++){
                        if ( i == left || i == right )
                                continue;
                        else
                                ind = i;
                }
                return ind;
        }
}

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.