cost={"apple":5.2,"山竹":12.9,"香蕉":2.4,"荔枝":15,"putao":9.3,"guiyuan":8,"lanmei":10,"李子":8}
k=input("请输入水果名称: ")
v=input("请输入水果价钱: ")
if k in cost:
    if float(v)<cost[k]:
        cost[k]=float(v)
        print(k+'降价了，现价'+v+'元')
    else:
        print(k+"涨价了，我们不买")
else:
    cost[k] =float(v)
    print(k+"的价钱"+v+"元已上传~")