题解 | #牛牛的绩点#
牛牛的绩点
http://www.nowcoder.com/practice/de8bc3e736164786b07a4dd64ed172f7
gl = {"A":4.0, "B":3.0, "C":2.0, "D":1.0, "F":0}
al = []
bl = []
while True:
g = input()
if g == "False":
break
else:
sco = int(input())
al.append(gl[g]*sco)
bl.append(sco)
print("%.2f" % (sum(al) / sum(bl)))
