Take Your Places! solution codeforces

Take Your Places! solution codeforces

William has an array of nn integers a1,a2,,ana1,a2,…,an. In one move he can swap two neighboring items. Two items aiai and ajaj are considered neighboring if the condition |ij|=1|i−j|=1 is satisfied.

William wants you to calculate the minimal number of swaps he would need to perform to make it so that the array does not contain two neighboring items with the same parity. Take Your Places! solution codeforces

Input

Each test contains multiple test cases. The first line contains the number of test cases tt (1t1041≤t≤104). Description of the test cases follows.

The first line of each test case contains an integer nn (1n105)(1≤n≤105) which is the total number of items in William’s array.

The second line contains nn integers a1,a2,,ana1,a2,…,an (1ai109)(1≤ai≤109) which are William’s array.

It is guaranteed that the sum of nn over all test cases does not exceed 105105.

Output Take Your Places! solution codeforces

For each test case output the minimal number of operations needed or 1−1 if it is impossible to get the array to a state when no neighboring numbers have the same parity.

Example
input T ake Your Places! solution codeforces

Copy
5
3
6 6 1
1
9
6
1 1 1 2 2 2
2
8 6
6
6 2 3 4 5 1
output Take Your Places! solution codeforces

Copy
1
0
3
-1
2
Note Take Your Places! solution codeforces

In the first test case the following sequence of operations would satisfy the requirements:

  1. swap(2, 3). Array after performing the operation: [6,1,6][6,1,6]

In the second test case the array initially does not contain two neighboring items of the same parity.

In the third test case the following sequence of operations would satisfy the requirements:

  1. swap(3, 4). Array after performing the operation: [1,1,2,1,2,2][1,1,2,1,2,2]
  2. swap(2, 3). Array after performing the operation: [1,2,1,1,2,2][1,2,1,1,2,2]
  3. swap(4, 5). Array after performing the operation: [1,2,1,2,1,2][1,2,1,2,1,2]

In the fourth test case it is impossible to satisfy the requirements.

In the fifth test case the following sequence of operations would satisfy the requirements:

  1. swap(2, 3). Array after performing the operation: [6,3,2,4,5,1][6,3,2,4,5,1]
  2. swap(4, 5). Array after performing the operation: [6,3,2,5,4,1][6,3,2,5,4,1]

Leave a Comment