def calc(ex): try: if type(float(ex)) == float: return float(ex) except: pass exp = ex z = [a.strip() for a in exp.split("(")] if len(z) > 1: for i in range(len(z)-1,0,-1): zz = [a.strip() for a in z[i].split(")",1)] if len(zz) > 1: tmp = calc(zz[0]) z[i-1]=(z[i-1]+str(tmp)+zz[1]) exp = z[i-1] else: print("input not correct") return -1 z = [a.strip() for a in exp.split("+")] print(z) if "" in z: print("input not correct") return -1 if len(z) > 1: tmp = calc(z[0]) for i in range(len(z)-1): print(i) tmp += calc(z[i+1]) return tmp #print(z) z = [a.strip() for a in exp.split("-")] if "" in z: print("input not correct") return -1 if len(z) > 1: tmp = calc(z[0]) #print('tmp',tmp,z[0]) for i in range(len(z)-1): tmp -= calc(z[i+1]) print(tmp) return tmp z = [a.strip() for a in exp.split("*")] if "" in z: print("input not correct") return -1 if len(z) > 1: tmp = calc(z[0]) for i in range(len(z)-1): tmp *= calc(z[i+1]) return tmp z = [a.strip() for a in exp.split("/")] if "" in z: print("input not correct") return -1 if len(z) > 1: tmp = calc(z[0]) for i in range(len(z)-1): tmp /= calc(z[i+1]) return tmp print("input not correct") return -1 #print(calc("1-2+6-4/3/3-8*8+3-6/3")) #print(calc("(4/5)+1/(1+3)")) #print(calc("4/((5+1))/(1+3)")) print(calc('1+2*2+3+4-5-6+7+8'))