用栈代码实现步骤1：将中缀表达式转换为后缀表达式 步骤2：计算中缀表达式

好的，关于您的第一个问题，以下是使用栈代码实现步骤1：将中缀表达式转换为后缀表达式的示例代码：

# 定义操作符优先级
priority = {'(': 1, '+': 2, '-': 2, '*': 3, '/': 3}

# 将中缀表达式转换为后缀表达式
def infix_to_postfix(expression):
    stack = []
    postfix_expression = []
    for char in expression:
        if char.isdigit():
            postfix_expression.append(char)
        elif char == '(':
            stack.append(char)
        elif char == ')':
            op = stack.pop()
            while op != '(':
                postfix_expression.append(op)
                op = stack.pop()
        else:
            while stack and priority[char] <= priority.get(stack[-1], 0):
                postfix_expression.append(stack.pop())
            stack.append(char)
    while stack:
        postfix_expression.append(stack.pop())
    return postfix_expression

# 定义计算后缀表达式的函数
def calculate_postfix(postfix_expression):
    stack = []
    for char in postfix_expression:
        if char.isdigit():
            stack.append(int(char))
        else:
            b = stack.pop()
            a = stack.pop()
            if char == '+':
                stack.append(a + b)
            elif char == '-':
                stack.append(a - b)
            elif char == '*':
                stack.append(a * b)
            elif char == '/':
                stack.append(a / b)
    return stack.pop()

# 示例
expression = '3*5+(6-2)/4'
postfix_expression = infix_to_postfix(expression)
print('中缀表达式:', expression)
print('后缀表达式:', ''.join(postfix_expression))
print('结果:', calculate_postfix(postfix_expression))

对于第二个问题，由于它需要先完成第一个问题的步骤1，因此请先完成步骤1再进行计算中缀表达式。