#include "BiTree.h"

bool BiTree::is_empty(BiTree *bt) {
    if(bt==nullptr) {
        return true;
    }
    return false;
}

bool BiTree::is_leaf(BiTree *bt) {
    if(bt->left==nullptr && bt->right==nullptr) {
        return true;
    }
    return false;
}

int BiTree::sum_leaf(BiTree *bt) {
    if(is_empty(bt)) {
        return 0;
    }
    if(is_leaf(bt)) {
        return bt->data;
    }
    return sum_leaf(bt->left)+sum_leaf(bt->right);
}