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javaclassmethodsreturnbinary-tree

Java method giving unexpected return


I'm working on Java Binary Search Tree, and I'm trying to use method findHelp() in find(). I'm expecting a return value of rt.getValue() (which is C2-112, as I print out right before return), but printing out findHelp() in help method returns null.

I couldn't find similar error online, so can someone help me figure out, or give a link to a similar issue?

Here is my code

private E findHelp(BinaryNode<Key, E> rt, Key k) {
        int compare = k.compareTo(rt.getKey()); 
        if (compare==0) {
            System.out.println(rt.getValue()); // I'm getting C2-112 here 
            return rt.getValue(); // so I expect a return of C2-112
        } else if (compare >0 ) {
            if (rt.getRight() == null) {
                return null;
            } else {
                findHelp(rt.getRight(), k);
            }
        } else {
            if (rt.getLeft() == null) {
                return null;
            } else {
                findHelp(rt.getLeft(), k);
            }
        }
        return null;
    } // 

public E find(Key k) {
        E tmp = findHelp(root, k); 
        System.out.println(tmp); // this prints null, not C2-112
        return findHelp(root, k); // and so I return null
    }

Solution

  • add a return before every findHelp(...)