45 00 00 50 00 00 00 00 01 11 6d 1f ac 1a bf fd e0 00 00 66
import sys def somme(paquet): somme=0 if(len(paquet)%2!=0): paquet.append(0) for i in range(0,int(len(paquet)/2)): mot=paquet[2*i]<<8 | paquet[2*i+1] somme += mot while somme>>16: somme=(somme>>16)+somme&0xffff return (~somme)&0xffff paquet=[] while True: try: for mot in input().split(): paquet.append(int(mot,16)) except EOFError: break print('somme='+format(somme(paquet),'04x'))