You are given a binary array nums
of length n
, a positive integer k
and a non-negative integer maxChanges
.
Alice plays a game, where the goal is for Alice to pick up k
ones from nums
using the minimum number of moves. When the game starts, Alice picks up any index aliceIndex
in the range [0, n - 1]
and stands there. If nums[aliceIndex] == 1
, Alice picks up the one and nums[aliceIndex]
becomes 0
(this does not count as a move). After this, Alice can make any number of moves (including zero) where in each move Alice must perform exactly one of the following actions:
j != aliceIndex
such that nums[j] == 0
and set nums[j] = 1
. This action can be performed at most maxChanges
times.x
and y
(|x - y| == 1
) such that nums[x] == 1
, nums[y] == 0
, then swap their values (set nums[y] = 1
and nums[x] = 0
). If y == aliceIndex
, Alice picks up the one after this move and nums[y]
becomes 0
.Return the minimum number of moves required by Alice to pick exactly k
ones.
Example 1:
Input: nums = [1,1,0,0,0,1,1,0,0,1], k = 3, maxChanges = 1
Output: 3
Explanation: Alice can pick up 3
ones in 3
moves, if Alice performs the following actions in each move when standing at aliceIndex == 1
:
nums[1]
becomes 0
. nums
becomes [1,1,1,0,0,1,1,0,0,1]
.j == 2
and perform an action of the first type. nums
becomes [1,0,1,0,0,1,1,0,0,1]
x == 2
and y == 1
, and perform an action of the second type. nums
becomes [1,1,0,0,0,1,1,0,0,1]
. As y == aliceIndex
, Alice picks up the one and nums
becomes [1,0,0,0,0,1,1,0,0,1]
.x == 0
and y == 1
, and perform an action of the second type. nums
becomes [0,1,0,0,0,1,1,0,0,1]
. As y == aliceIndex
, Alice picks up the one and nums
becomes [0,0,0,0,0,1,1,0,0,1]
.Note that it may be possible for Alice to pick up 3
ones using some other sequence of 3
moves.
Example 2:
Input: nums = [0,0,0,0], k = 2, maxChanges = 3
Output: 4
Explanation: Alice can pick up 2
ones in 4
moves, if Alice performs the following actions in each move when standing at aliceIndex == 0
:
j == 1
and perform an action of the first type. nums
becomes [0,1,0,0]
.x == 1
and y == 0
, and perform an action of the second type. nums
becomes [1,0,0,0]
. As y == aliceIndex
, Alice picks up the one and nums
becomes [0,0,0,0]
.j == 1
again and perform an action of the first type. nums
becomes [0,1,0,0]
.x == 1
and y == 0
again, and perform an action of the second type. nums
becomes [1,0,0,0]
. As y == aliceIndex
, Alice picks up the one and nums
becomes [0,0,0,0]
.
Constraints:
2 <= n <= 105
0 <= nums[i] <= 1
1 <= k <= 105
0 <= maxChanges <= 105
maxChanges + sum(nums) >= k