(fpexp)
| 9 | |
| 10 | # 构造解析树 |
| 11 | def buildParseTree(fpexp): |
| 12 | fplist = fpexp.split() |
| 13 | pStack = Stack() |
| 14 | eTree = BinaryTree('') |
| 15 | pStack.push(eTree) |
| 16 | currentTree = eTree |
| 17 | for i in fplist: |
| 18 | if i == '(': |
| 19 | currentTree.insertLeft('') |
| 20 | pStack.push(currentTree) |
| 21 | currentTree = currentTree.getLeftChild() |
| 22 | elif i not in ['+', '-', '*', '/', ')']: |
| 23 | currentTree.setRootVal(int(i)) |
| 24 | parent = pStack.pop() |
| 25 | currentTree = parent |
| 26 | elif i in ['+', '-', '*', '/']: |
| 27 | currentTree.setRootVal(i) |
| 28 | currentTree.insertRight('') |
| 29 | pStack.push(currentTree) |
| 30 | currentTree = currentTree.getRightChild() |
| 31 | elif i == ')': |
| 32 | currentTree = pStack.pop() |
| 33 | else: |
| 34 | raise ValueError |
| 35 | return eTree |
| 36 | |
| 37 | # 递归实现两个叶结点的运算 |
| 38 | def evaluate(parseTree): |
no test coverage detected