图求最短路径

class DeepTrace{public:    void InitMap(const vector<vector<int> > vMap, const int &portNum)    {        m_map = vMap;        m_portNum = portNum;        m_traceTree.clear();    }    bool GetRule(const int &beginPos, const int &endPos, list<int> &rules)    {        if(beginPos <0 || beginPos >= m_portNum)            return false;        if(endPos <0 || endPos >= m_portNum)            return false;        m_traceTree.clear();        vector<bool> hasWalk(m_portNum, false);        queue<int> q; q.push(beginPos);        m_traceTree.push_back(make_pair(beginPos, -1));        int nPos = 0;        while(!q.empty())        {            int nowPos = q.front(); q.pop();            hasWalk[nowPos] = true;            if(nowPos == endPos)            {                print_rule(nPos, rules);                return true;            }            vector<int> tmp = m_map[nowPos];            vector<int> :: const_iterator pos = tmp.begin();            const int parent = nPos;//m_traceTree.size() - 1;            for(;pos != tmp.end(); ++pos)            {                if(false == hasWalk[*pos])                {                    q.push(*pos);                    m_traceTree.push_back(make_pair(*pos,parent));                }            }            ++nPos;        }        return false;    }private://nPos是树的位置， 从树的某个节点开始，回溯到开始节点    void print_rule(int nPos, list<int> &rules)    {        if(nPos < 0 || nPos >= m_traceTree.size())            return;        int index = 0;        do        {            rules.push_front(m_traceTree[nPos].first);            ++index;            nPos = m_traceTree[nPos].second;            //for(int i= 0; i < 11; i++)                //cout<< m_traceTree[i].first << m_traceTree[i].second <<endl;            //cout<< "npos " << nPos <<endl;;        }while(index <= m_traceTree.size() && m_traceTree[nPos].second != -1);        return;    }    vector<vector<int> > m_map;    int m_portNum;    vector<pair<int, int> > m_traceTree; //valie ,parentindex};int main(){    vector<int> tmp;    vector<vector<int > > vMap;    //0    tmp.push_back(1);    tmp.push_back(2);    vMap.push_back(tmp);    //1    tmp.clear();    tmp.push_back(3);    tmp.push_back(5);    vMap.push_back(tmp);    //2    tmp.clear();    tmp.push_back(0);    tmp.push_back(3);    vMap.push_back(tmp);    //3    tmp.clear();    tmp.push_back(1);    tmp.push_back(2);    tmp.push_back(4);    tmp.push_back(6);    vMap.push_back(tmp);    //4    tmp.clear();    tmp.push_back(3);    tmp.push_back(7);    vMap.push_back(tmp);    //5    tmp.clear();    tmp.push_back(1);    tmp.push_back(6);    vMap.push_back(tmp);    //6    tmp.clear();    tmp.push_back(3);    tmp.push_back(5);    tmp.push_back(7);    vMap.push_back(tmp);    //7    tmp.clear();    tmp.push_back(4);    tmp.push_back(6);    vMap.push_back(tmp);    DeepTrace obj;    obj.InitMap(vMap, 8);    list<int> listRules;    bool findit = obj.GetRule(0, 7, listRules);    list<int> ::const_iterator pos = listRules.begin();    cout<< "----------" <<endl;    for(; pos != listRules.end(); ++pos)    {        cout<< *pos << " " <<endl;    }

图的数据结构组织形式：
vector < vector< int > >
0-》1，2
1-》3,5
2-》0,3
3-》1,2,4,6
4-》3,7
5-》1,6
6-》3,5,7
7-》4,6