Java OCA OCP Practice Question 1152

Question

What will the following program print? 

public class Main{ 
    public static void main (String args [])  { 
        int counter = 0; 
        outer: /*from w w  w. j  a  v  a2  s  . c om*/
        for  (int i = 0; i < 3; i++)  { 
            middle: 
            for  (int j = 0; j < 3; j++)  { 
                inner: 
                for  (int k = 0; k < 3; k++)  { 
                    if  (k - j > 0)  { 
                        break middle; 
                     } 
                    counter++; 
                 } 
             } 
         } 
        System.out.println (counter); 
     } 
}

Select 1 option

  • A. 2
  • B. 3
  • C. 6
  • D. 7
  • E. 9 


Correct Option is  : B

Note

To understand how this loop works let us put some extra print statements in the innermost loop : 

System.out.println ("i="+i+" j="+j+" k="+k); 
if (k-j>0){ 
     System.out.println ("breaking middle "+j); 
     break middle; 
} 
counter++;

This is what it prints: 

i=0 j=0 k=0 /*from  ww w  . j av a  2 s. c o m*/
i=0 j=0 k=1 
breaking middle 0 
i=1 j=0 k=0 
i=1 j=0 k=1 
breaking middle 0 
i=2 j=0 k=0 
i=2 j=0 k=1 
breaking middle 0 
3

The key is that the middle loop is broken as soon as k-j becomes > 0.

This happens on every second iteration of inner loop when k is 1 and j is 0.

When middle is broken inner cannot continue. So the next iteration of outer starts.




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