x='' dict={'A':4.0,'B':3.0,'C':2.0,'D':1.0,'F':0} list=[] result,even=0,0 i=0 while True: x=input() if x in dict.keys(): list.append(dict[x]) elif x=='False': break else: list.append(int(x)) for j in range(len(list)//2): result += list[i]*list[i+1] even += list[i+1] i += 2 print('%.2f'%(result/even)...
