# 1151 Minimum Swaps to Group All 1's Together

Given a binary array `data`, return the minimum number of swaps required to group all `1`â€™s present in the array together in any place in the array.

Example 1:

``````Input: data = [1,0,1,0,1]
Output: 1
Explanation: There are 3 ways to group all 1's together:
[1,1,1,0,0] using 1 swap.
[0,1,1,1,0] using 2 swaps.
[0,0,1,1,1] using 1 swap.
The minimum is 1.
``````

Example 2:

``````Input: data = [0,0,0,1,0]
Output: 0
Explanation: Since there is only one 1 in the array, no swaps are needed.
``````

Example 3:

``````Input: data = [1,0,1,0,1,0,0,1,1,0,1]
Output: 3
Explanation: One possible solution that uses 3 swaps is [0,0,0,0,0,1,1,1,1,1,1].
``````

Constraints:

• `1 <= data.length <= 105`
• `data[i]` is either `0` or `1`.
 `````` 1 2 3 4 5 6 7 8 9 10 11 12 13 `````` ``````class Solution: def minSwaps(self, data: List[int]) -> int: ones = sum(data) count, max_one = 0, 0 l = r = 0 while r < len(data): count += data[r] r += 1 if r - l > ones: count -= data[l] l += 1 max_one = max(max_one, count) return ones - max_one``````