A time to scatter stones#347
On the table, there are boxes arranged in a row. Each box is either empty or contains a certain number of pebbles. In one move, you can perform one of the following actions:
Take one pebble from an end box and move it to the adjacent box.
Take two pebbles from a box that is not at the end and place one pebble in each of its neighboring boxes.
Your task is to determine whether it is possible to achieve a certain target arrangement of pebbles in the boxes using these operations, and if it is possible, to determine the minimum number of moves required.
The first line contains a single natural number (2 \leq N \leq 20) — the number of boxes.
The second line contains non-negative integers a_i separated by spaces, where a_i is the current number of pebbles in the -th box (0 \leq a_i \leq 100). The total sum of all a_i does not exceed .
The third line contains non-negative integers b_i separated by spaces, where b_i is the desired number of pebbles in the -th box (0 \leq b_i \leq 100).
If it is not possible to achieve the desired arrangement, output No solution in the first line. Otherwise, output a single integer — the minimum number of moves required to reach the desired configuration.
Example 1