add new solutions

solutions/1/q108/solution.go

@@ -0,0 +1,26 @@
+package q108
+
+type TreeNode struct {
+	Val   int
+	Left  *TreeNode
+	Right *TreeNode
+}
+
+func sortedArrayToBST(nums []int) *TreeNode {
+	if len(nums) == 0 {
+		return nil
+	}
+	if len(nums) == 1 {
+		return &TreeNode{Val: nums[0]}
+	}
+
+	l, r := nums[:len(nums)/2], nums[len(nums)/2+1:]
+	m := nums[len(nums)/2]
+	return &TreeNode{
+		Val:   m,
+		Left:  sortedArrayToBST(l),
+		Right: sortedArrayToBST(r),
+	}
+}
+
+var _ = sortedArrayToBST

solutions/1/q120/solution.go

@@ -0,0 +1,14 @@
+package q120
+
+func minimumTotal(triangle [][]int) int {
+	size := len(triangle)
+
+	for row := size - 2; row >= 0; row-- {
+		for i := range triangle[row] {
+			triangle[row][i] += min(triangle[row+1][i], triangle[row+1][i+1])
+		}
+	}
+	return triangle[0][0]
+}
+
+var _ = minimumTotal

solutions/1/q136/solution.go

@@ -0,0 +1,11 @@
+package q136
+
+func singleNumber(nums []int) int {
+	x := 0
+	for _, num := range nums {
+		x ^= num
+	}
+	return x
+}
+
+var _ = singleNumber

solutions/1/q190/solution.go

@@ -0,0 +1,13 @@
+package q190
+
+func reverseBits(n int) int {
+	ret := 0
+	for i := range 32 {
+		if n|(1<<i) == n {
+			ret |= 1 << (31 - i)
+		}
+	}
+	return ret
+}
+
+var _ = reverseBits

solutions/1/q191/solution.go

@@ -0,0 +1,13 @@
+package q191
+
+func hammingWeight(n int) int {
+	num := 0
+	for ; n > 0; n >>= 1 {
+		if n|1 == n {
+			num++
+		}
+	}
+	return num
+}
+
+var _ = hammingWeight