Tree on the level UVa122

很单纯的树的遍历，但是输入和方向好麻烦！！
下面给出代码，题目来自UVa 122

 #include<cstdio>
 #include<cstring>
 #include<vector>
 #include<cstdlib>
 #include<queue>
 using namespace std;
  + ;
 struct Node{
     bool have_value;
     int v;
     Node *right,*left;
     Node():have_value(false),right(NULL),left(NULL){}
 };
 Node *root;
 Node* newnode(){return new Node();}

 void remove_tree(Node* u){     //防止内存泄露。 但可能会出现内存碎片
     if(u == NULL)return;
     remove_tree(u->left);
     remove_tree(u->right);
     delete u;
 }

 char s[maxn];
 bool failed;
 void addnode(int v,char *s){
     int len = strlen(s);
     Node* u = root;
     ; i < len;i++){
         if(s[i] == 'L'){
             if(u->left == NULL)u->left = newnode();
             u = u->left;
         }
         else if(s[i] == 'R'){
             if(u->right == NULL)u->right = newnode();
             u = u->right;
         }
     }
     if(u->have_value)failed = true;
     u->v = v;
     u->have_value = true;// 标记！！ 

 }
 bool read_input(){
     failed = false;
     remove_tree(root);
     root = newnode();
     for(;;){
          ) return false;
         if(!strcmp(s,"()"))break;                //记住！！strcmp函数中的第二个参数是字符串！！
         int v;
         sscanf(&s[],"%d", &v);                    //&s[1]所对应的字符串是从s[1]后的字符串
         addnode(v,strchr(s,);                //函数strchr（s,','）返回字符串s中从左往右第一个字符","的指针
     }
     return true;
 }
 bool bfs(vector<int>& ans){                    //bfs遍历树
     queue<Node*> q;
     ans.clear();
     q.push(root);
     while(!q.empty()){
         Node* u = q.front();q.pop();
         if(!u->have_value)return false;        //判断是否输入错误
         ans.push_back(u->v);
         if(u->left != NULL)q.push(u->left);
         if(u->right != NULL)q.push(u->right);
     }
     return true;

 }

 int main(){
     freopen("tree.txt","r",stdin);
     freopen("treeout.txt","w",stdout);
     vector<int> ans;
     while(read_input()){
         ;        // 参数！！
         if(failed)printf("-1\n");
         else{
             ; i < ans.size();i++){
                 if(i)printf(" ");
                 printf("%d", ans[i]);
             }
             printf("\n"); 

         }
     }
     ;
 }