import re def repeat_func(s): #去掉重复的+——号 repeat = re.findall(‘\+\-|\-\-|\++\-\+‘, s) if len(repeat) > 0: for i in repeat: if i == ‘--‘ or i == ‘++‘: s = s.replace(i, ‘+‘) if i == ‘+-‘ or s == ‘-+‘: s = s.replace(i, ‘-‘) return s def mul_devid(content): # 计算乘除 pattern1 = ‘-?\d+\.?\d*(?:\*|\/)-?\d+\.?\d*‘ while 1: first = re.search(pattern1, content) #匹配乘除 if first: if ‘*‘ in first.group(): new1 = first.group().split(‘*‘) new = float(new1[0]) * float(new1[1]) new = str(new) else: new1 = first.group().split(‘/‘) new = float(new1[0]) / float(new1[1]) new = str(new) res=re.search(r‘-\d+\.?\d*(?:\*|\/)-\d+\.?\d*‘,content) #如果两个负数相乘或相除,添加正号 if res : new=‘+‘ + new content = repeat_func(content) content = content.replace(first.group(), new) else: break return content def add_minus(content): # 计算加减 pattern2 = ‘-?\d+\.?\d*(?:\+|\-)\d+\.?\d*‘ while 1: first = re.search(pattern2, content) if first: #根据不同的模式分别计算 choice1 = re.search(‘(-\d+\.?\d*-\d+\.?\d*)‘, first.group()) if choice1: new1 = first.group().split(‘-‘) new = -(float(new1[1]) + float(new1[2])) choice2 = re.search(‘(-\d+\.?\d*\+\d+\.?\d*)|(\d+\.?\d*\+\d+\.?\d*)‘, first.group()) if choice2: new1 = first.group().split(‘+‘) new = float(new1[1]) + float(new1[0]) choice3 = re.search(‘\d+\.?\d*-\d+\.?\d*‘, first.group()) if choice3: new1 = first.group().split(‘-‘) new = float(new1[0]) - float(new1[1]) # # content=repeat_func(content) content = content.replace(first.group(), str(new)) else: break return content def calculate(content): content = mul_devid(content) content = add_minus(content) return content def bracket(s): while 1: first = re.search(r‘\([^()]+\)‘, s) if first: new=calculate(first.group()) s=s.replace(first.group(),new[1:-1]) s=repeat_func(s) else: break end=calculate(s) return end s=‘1-2*((60-30+(-40/5)*(9-2*5/3+7/3*99/4*2998+10*568/14))-(-4*3)/(16-3*2))‘ print(eval(s)) print(bracket(s))
时间: 2024-12-28 21:26:20