Ovuvuevuevue Enyetuenwuevue Ugbemugbem Osas is a shopaholic.
There are n different kinds of items in a store and Osas wants to buy every kinds of them.
The i-th item cost ai dollars, but the price fluctuates greatly recently.
Tomorrow the i-th item's price will be bi dollars. Osas has an special ability that he can know the price tomorrow.
Because he's a shopaholic, he wants to buy every kinds of items in at most two days. Osas must buy at least k item at first day, or he will be crazy.
Help Osas find out the minimum money he should pay to buy every kinds of item in the shop.
Input contains third lines.
First line contains two integer n ( 1 <= n <= 105 ) and k ( 0 <= k <= n ).
Second line contains n integer a1 ~ an ( 1 <= ai <= 105).
Third line contains n integer b1 ~ bn ( 1 <= bi <= 105 ).
Output only contains one integer -- the minimum price Osas needs to pay.