# Hello World! : ++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>. #SoloLearn only accepts 100-char input, #so you may have to copy these code on #another python compiler for longer codes. import re s = str(input()).replace(' ','') print('Input brainfuck code: ' + s) if re.match(r'^[\>\<\+\-\[\]\,\.]+$',s) is None: print('Invalid Input, a brainfuck code should only contain "+-><[],."') else: x = 0 ft = '' for a in s: if a == '[': x += 1 elif a == ']': if x ==0: ft += '[' else: x -= 1 s = ft + s + ']'*x #fix bracket list = [0] index = 0 outputs = '' p = 0 inputs = '' index2 = 0 if ',' in s: inputs = str(input()) #for input string cfl = [] #for infinite loops check while p < len(s): if s[p] == '+': list[index] += 1 elif s[p] == '-': if list[index] == 0: print('ERROR: value less than 0') break else: list[index] -= 1 elif s[p] == '>': if index == len(list)-1: list.append(0) index += 1 elif s[p] == '<': if index == 0: print('ERROR: index less than 0') break else: index -= 1 elif s[p] == ',': if index2 < len(inputs): list[index] = ord(inputs[index2]) index2 += 1 else: print('result: '+outputs+'\nbreak due to insufficient input') break elif s[p] == '.': if list[index] < 128: outputs += chr(list[index]) else: print('ERROR: char value over 127') break elif s[p] == '[': cfs = '' x = 0 tempIndex = p+1 while x>=0: if s[tempIndex]=='[': x += 1 elif s[tempIndex]==']': x -= 1 cfs += s[tempIndex] tempIndex += 1 if ',' not in cfs: cfl.append([p,tempIndex-1,index,list[index]]) elif s[p] == ']': if len(cfl)>0 and cfl[-1][1]==p: if list[index] >= cfl[-1][3]: print('ERROR: infinite loop at ' + str(cfl[-1][0:2]) + ' : ' + s[cfl[-1][0]:cfl[-1][1]+1]) break else: del cfl[-1] if list[index] > 0: x = 0 while x>=0: p -= 1 if s[p]==']': x += 1 elif s[p]=='[': x -= 1 p += 1 print('Output: ' + outputs) print('Last data: ' + str(list))

Brainf**k interpreter