From a72be2f90545df5dfce8b8a998a587948cc7e63c Mon Sep 17 00:00:00 2001
From: mq67zk3g5 <1754970961@qq.com>
Date: Sun, 10 Jul 2022 00:17:54 +0800
Subject: [PATCH] ADD file via upload

---
 四则运算计算器.py | 160 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 160 insertions(+)
 create mode 100644 四则运算计算器.py

diff --git a/四则运算计算器.py b/四则运算计算器.py
new file mode 100644
index 0000000..34053ea
--- /dev/null
+++ b/四则运算计算器.py
@@ -0,0 +1,160 @@
+
+# 四则运算行棋      计算器
+"""|||mid_to_aft：将中缀表达式转化为后缀表达式l;
+aft_to_cal：有参数l，将后缀表达式进行计算；
+mid_to_cal：直接将中缀表达式进行计算。|||"""
+
+
+class Calculator(object):  # 用一个类应用于计算
+    def __init__(self, equ):
+        self.s = equ
+
+    def mid_to_aft(self):
+        pref = {'+': 1, '-': 1, '*': 2, '/': 2, '^': 3}  # 符号字典
+        l = ''
+        A = []
+        i = 0
+        while True:
+            loc = self.s[i]
+            # 可能是一个两位以上的数字
+            if loc in list('0123456789'):
+                while i < len(self.s) - 1 and self.s[i + 1] in list('0123456789'):  # 不是最后一个数字且为连续数字
+                    loc += self.s[i + 1]
+                    i += 1  # 刚好到连续的最后一个数字
+                l = l + loc + ' '
+            elif loc in list('()+-*/^'):
+                if A == [] or loc == '(':
+                    A.append(loc)
+                elif loc == ')':
+                    while A[-1] != '(':
+                        l = l + A.pop() + ' '
+                    A.pop()
+                elif A[-1] == '(':
+                    A.append(loc)
+                else:
+                    if pref[loc] > pref[A[-1]]:
+                        A.append(loc)
+                    else:
+                        while A[-1] != '(':
+                            l = l + A.pop() + ' '
+                            if A == []:
+                                break
+                        A.append(loc)
+            i += 1
+            if i == len(self.s):
+                while A != []:
+                    if len(A) == 1:
+                        l += A.pop()
+                    else:
+                        l = l + A.pop() + ' '
+                break
+        return l
+
+    def aft_to_cal(self, l):
+        A = []
+        i = 0
+        while True:
+            # print('第{}个元素：A = '.format(i+1),A)
+            loc = l[i]
+            if loc in list('0123456789'):
+                while l[i + 1] in list('0123456789'):  # 此时肯定是数字
+                    loc += l[i + 1]
+                    i = i + 1
+                A.append(float(loc))
+                i += 1
+            elif loc == ' ':
+                i += 1
+                continue
+            else:
+                if loc == '+':
+                    A.append(A.pop() + A.pop())
+                elif loc == '-':
+                    A.append(-A.pop() + A.pop())
+                elif loc == '*':
+                    A.append(A.pop() * A.pop())
+                elif loc == '/':
+                    A.append((1 / A.pop()) * A.pop())
+                else:
+                    last = A.pop()
+                    A.append(pow(A.pop(), last))
+                i += 1
+            if i >= len(l) - 1:
+                break
+        result = A.pop()
+        return result
+
+    def mid_to_cal(self):
+        pref = {'+': 1, '-': 1, '*': 2, '/': 2, '^': 3}
+        l = ''
+        A = []
+        i = 0
+        while True:
+            loc = self.s[i]
+            # 可能是一个两位以上的数字
+            if loc in list('0123456789'):
+                while i < len(self.s) - 1 and self.s[i + 1] in list('0123456789'):  # 不是最后一个数字且为连续数字
+                    loc += self.s[i + 1]
+                    i += 1  # 刚好到连续的最后一个数字
+                l = l + loc + ' '
+            elif loc in list('()+-*/^'):
+                if A == [] or loc == '(':
+                    A.append(loc)
+                elif loc == ')':
+                    while A[-1] != '(':
+                        l = l + A.pop() + ' '
+                    A.pop()
+                elif A[-1] == '(':
+                    A.append(loc)
+                else:
+                    if pref[loc] > pref[A[-1]]:
+                        A.append(loc)
+                    else:
+                        while A[-1] != '(':
+                            l = l + A.pop() + ' '
+                            if A == []:
+                                break
+                        A.append(loc)
+            i += 1
+            if i == len(self.s):
+                while A != []:
+                    if len(A) == 1:
+                        l += A.pop()
+                    else:
+                        l = l + A.pop() + ' '
+                break
+        i = 0
+        while True:
+            loc = l[i]
+            if loc in list('0123456789'):
+                while l[i + 1] in list('0123456789'):  # 此时肯定是数字
+                    loc += l[i + 1]
+                    i = i + 1
+                A.append(float(loc))
+                i += 1
+            elif loc == ' ':
+                i += 1
+                continue
+            else:
+                if loc == '+':
+                    A.append(A.pop() + A.pop())
+                elif loc == '-':
+                    A.append(-A.pop() + A.pop())
+                elif loc == '*':
+                    A.append(A.pop() * A.pop())
+                elif loc == '/':
+                    A.append((1 / A.pop()) * A.pop())
+                else:
+                    last = A.pop()
+                    A.append(pow(A.pop(), last))
+                i += 1
+            if i >= len(l) - 1:
+                break
+        result = A.pop()
+        return result
+
+
+'''def eval(expression):
+    c = eval(expression)
+    return c'''
+
+'''中缀转后缀计算器设计结束'''
\ No newline at end of file