This is my program, can anybody tell me what is wrong?
I did lot of tests and it seems to work, but I get WA.
pleeeeaaaasssssseeeeeee, help!!!!!

#include <iostream.h>
#include <fstream.h>

#ifndef ONLINE_JUDGE
ifstream in("in.txt");
ofstream out("out.txt");
#else
#define in cin
#define out cout
#endif

int max(int a,int b)
{
    return a>b?a:b;
}

class PreNode
{
public:
    PreNode():_size(0){}
    Add(int n)
    {
        _branch[_size++] = n;
    }
    int _size;
    int _branch[3];
};

class Node
{
public:
    Node()
    {
        _child[0] = NULL;
        _child[1] = NULL;
    }
    int _apples;
    int _maxBranches;
    int _maxApples[101];
    Node *_child[2];
    void GetVect();
    void AddOneChild(Node *child)
    {
        _maxBranches = child->_maxBranches+1;
        for(int i = 0;i<=child->_maxBranches;i++)
            _maxApples[i+1] =
child->_maxApples[i]+_apples;
    }
};

PreNode preTree[101];
int apples[101][101];
Node tree[101];
int N,Q;

void Make(int n,int p)
{
    int hijo = 0;
    tree[n]._apples = apples[p][n];
    for(int i = 0;i<preTree[n]._size;i++)
    {
        if(preTree[n]._branch[i] != p)
        {
            tree[n]._child[hijo++] =
&tree[preTree[n]._branch[i]];
            Make(preTree[n]._branch[i],n);
        }
    }
}

void Node::GetVect()
{
    for(int h = 0;h<2;h++)
    {
        if(_child[h] != NULL)
            _child[h]->GetVect();
    }
    _maxApples[0] = _apples;
    if(_child[0] == NULL && _child[1] == NULL)
        _maxBranches = 0;
    else
    {
        if(_child[0] != NULL && _child[1] == NULL)
            AddOneChild(_child[0]);
        else
        {
            if(_child[1] != NULL && _child[0] ==
NULL)
                AddOneChild(_child[1]);
            else
            {
                _maxBranches =
2+_child[0]->_maxBranches+_child[1]->_maxBranches;
                for(int i = 1 ; i<=
_maxBranches;i++)
                {
                    int maxi = 0;

if(_child[0]->_maxBranches >= i-1)
                        maxi =
max(maxi,_child[0]->_maxApples[i-1]+_apples);

if(_child[1]->_maxBranches >= i-1)
                        maxi =
max(maxi,_child[1]->_maxApples[i-1]+_apples);
                    for(int j =
0;j<=i-2;j++)
                    {

if(_child[0]->_maxBranches >= j && _child[0]->_maxBranches
>= (i-2-j))
                        {
                            maxi
=
max(maxi,_child[0]->_maxApples[j]+_child[1]->_maxApples[i-2-
j]+_apples);

                        }
                    }
                    _maxApples[i] =
maxi;
                }
            }
        }
    }
}

int main()
{
    int i;
   in >> N;
   in >> Q;
   for(i=0;i<N-1;i++)
   {
       int f,t,m;
       in >> f >> t >> m;
       apples[f][t] = m;
       apples[t][f] = m;
       preTree[f].Add(t);
       preTree[t].Add(f);
   }

    tree[1]._apples = 0;
    Make(1,-1);
    tree[1].GetVect();
    out << tree[1]._maxApples[Q];
   return 0;
}