uncommited problems

wiggle-subsequence/sol.go

@@ -0,0 +1,17 @@
+package main
+
+func wiggleMaxLength(nums []int) int {
+	// Current's value only matters in terms of negative / 0 / positive.
+	// The numerical value doesn't get used and therefore can be messed with.
+	current, count := 0, len(nums)
+	for i := 0; i < len(nums)-1; i++ {
+		new := nums[i+1] - nums[i]
+		if (current > 0 && new > 0) || (current < 0 && new < 0) || new == 0 {
+			count--
+		}
+		if new != 0 {
+			current = new
+		}
+	}
+	return count
+}