java版数据结构的 算术表达式与二叉树源码

/* int k=0; if (k != a.length) { ThrNode node =new ThrNode(a[k]); t =pnode; k++; if ((a[k-1] >= '0' && a[k-1] <= '9') || (a[k-1] >= 'a' && a[k-1] <= 'z')) { t.lchild = null; t.rchild = null; } else { CreateTree(t.lchild); CreateTree(t.rchild); } }*/ /*Stack<ThrNode> st = new Stack<ThrNode>(); ThrNode pnode = tn; boolean flag = true; char ch; int i = 0; while (i < a.length) { ch = a[i]; while (true) { if ("#".equals(a[i])) { pnode = st.pop(); if (pnode.flag == false) { pnode.lchild = null; pnode.flag = true; st.push(pnode); } else { pnode.rchild = null; } // 记得加1 i++; break; } if (pnode.flag == true) { pnode.rchild = new ThrNode(); pnode = pnode.rchild; } pnode.data = a[i]; st.push(pnode); pnode.lchild = new ThrNode(); pnode = pnode.lchild; i++; } if (pnode.flag == false) { st.push(pnode); pnode.flag = true; pnode = pnode.rchild; } else { pnode = st.peek(); pnode.flag = true; } i++; }*/