Devu是一位著名的古典歌手。他被邀请参加许多大型活动/节日。最近，他被邀请参加 "全世界古典歌唱节"。除Devu外，喜剧演员Churu也被邀请。
Devu已经向组织者提供了一份歌曲清单和所需的演唱时间。他将演唱N首歌曲，每首歌曲都需要精确的时间。
喜剧演员Churu将讲笑话。他的所有笑话都是5分钟的。
人们主要是来听Devu的。但你知道，他在每首歌之后需要休息10分钟。另一方面，Churu是一个非常活跃的人，不需要任何休息。
作为组织者之一，你应该为活动制定一个最佳时间表。由于某些原因，您必须遵循这些条件。
活动的时间不能超过d分钟。
Devu必须完成他的所有歌曲。
在满足前面两个条件的情况下，Churu所讲的笑话数量应尽可能多。
如果不可能找到一个方法来进行Devu的所有歌曲，则输出-1。否则，找出Churu在盛会中能开出的最大笑话数。
Devu is a renowned classical singer. He is invited to many big functions/festivals. Recently he was invited to "All World Classical Singing Festival". Other than Devu, comedian Churu was also invited.
Devu has provided organizers a list of the songs and required time for singing them. He will sing
n songs,
ith song will take
ti minutes exactly.
The Comedian, Churu will crack jokes. All his jokes are of 5 minutes exactly.
People have mainly come to listen Devu. But you know that he needs rest of 10 minutes after each song. On the other hand, Churu being a very active person, doesn't need any rest.
You as one of the organizers should make an optimal schedule for the event. For some reasons you must follow the conditions:
-
The duration of the event must be no more than d minutes;
-
Devu must complete all his songs;
-
With satisfying the two previous conditions the number of jokes cracked by Churu should be as many as possible.
If it is not possible to find a way to conduct all the songs of the Devu, output -1. Otherwise find out maximum number of jokes that Churu can crack in the grand event.
Note
Consider the first example. The duration of the event is
30 minutes. There could be maximum
5 jokes in the following way:
-
First Churu cracks a joke in 5 minutes.
-
Then Devu performs the first song for 2 minutes.
-
Then Churu cracks 2 jokes in 10 minutes.
-
Now Devu performs second song for 2 minutes.
-
Then Churu cracks 2 jokes in 10 minutes.
-
Now finally Devu will perform his last song in 1 minutes.
Total time spent is
5+2+10+2+10+1=30 minutes.
Consider the second example. There is no way of organizing Devu's all songs. Hence the answer is -1.