sum all odd in binary search tree recursion javascript
function sumOfAllOdd(BT) {
if (BT.isEmpty()) return 'empty BT';
function _sumOdd(node, sum = 0) {
if (node === null) {
return 0;
} else {
if (node.value % 2 != 0) {
sum += node.value;
}
}
return sum + _sumOdd(node.left) + _sumOdd(node.right);
}
return _sumOdd(BT.root);
}