feat(leetcode): add No.1005

Author: mickey0524

1005.Maximize-Sum-Of-Array-After-K-Negations.go

@@ -0,0 +1,52 @@
+// https://leetcode.com/problems/maximize-sum-of-array-after-k-negations/
+//
+// algorithms
+// Easy (45.09%)
+// Total Accepted:    2,968
+// Total Submissions: 6,582
+// beats 100.0% of golang submissions
+
+package leetcode
+
+import "sort"
+
+func largestSumAfterKNegations(A []int, K int) int {
+	length := len(A)
+
+	sort.Sort(sort.IntSlice(A))
+	i := 0
+
+	for K > 0 && i < length {
+		if A[i] >= 0 {
+			break
+		}
+		A[i] = -A[i]
+		i++
+		K--
+	}
+
+	if K == 0 || i == length || A[i] == 0 {
+		return sum(A)
+	}
+
+	K %= 2
+	if K == 1 {
+		if i > 0 && A[i] > A[i-1] {
+			A[i-1] = -A[i-1]
+		} else {
+			A[i] = -A[i]
+		}
+	}
+
+	return sum(A)
+}
+
+func sum(A []int) int {
+	res := 0
+
+	for _, n := range A {
+		res += n
+	}
+
+	return res
+}