add new files

Author: anakin

66. Plus One.go

@@ -0,0 +1,17 @@
+package main
+
+func plusOne(digits []int) []int {
+
+	l := len(digits)
+	for i := l - 1; i >= 0; i-- {
+		if digits[i] < 9 {
+			digits[i]++
+			return digits
+		}
+		digits[i] = 0
+	}
+	//如果有进位
+	res := []int{1}
+	res = append(res, digits...)
+	return res
+}

70. Climbing Stairs.go

@@ -0,0 +1,13 @@
+package main
+
+//DP
+func climbStairs(n int) int {
+	if n < 2 {
+		return 1
+	}
+	tmp := []int{1, 2}
+	for i := 2; i < n; i++ {
+		tmp = append(tmp, tmp[i-1]+tmp[i-2])
+	}
+	return tmp[n-1]
+}

77. Combinations.go

@@ -0,0 +1,21 @@
+package main
+
+func combine(n int, k int) [][]int {
+	var res [][]int
+	helper(&res, []int{}, 1, n, k)
+	return res
+}
+
+func helper(res *[][]int, coms []int, start int, n int, k int) {
+	if k == 0 {
+		tmp := []int{}
+		tmp = append(tmp, coms...)
+		*res = append(*res, tmp)
+		return
+	}
+	for i := start; i <= n; i++ {
+		coms = append(coms, i)
+		helper(res, coms, i+1, n, k-1)
+		coms = coms[:len(coms)-1]
+	}
+}

83. Remove Duplicates from Sorted List.go

@@ -0,0 +1,18 @@
+package main
+
+type ListNode struct {
+	Val  int
+	Next *ListNode
+}
+
+func deleteDuplicates(head *ListNode) *ListNode {
+	cur := head
+	for cur != nil && cur.Next != nil {
+		if cur.Next.Val == cur.Val {
+			cur.Next = cur.Next.Next
+		} else {
+			cur = cur.Next
+		}
+	}
+	return head
+}

86. Partition List.go

@@ -0,0 +1,28 @@
+package main
+
+type ListNode struct {
+	Val  int
+	Next *ListNode
+}
+
+//新建两个列表
+func partition(head *ListNode, x int) *ListNode {
+
+	beforehead := &ListNode{}
+	before := beforehead
+	afterhead := &ListNode{}
+	after := afterhead
+	for head != nil {
+		if head.Val < x {
+			before.Next = head
+			before = before.Next
+		} else {
+			after.Next = head
+			after = after.Next
+		}
+		head = head.Next
+	}
+	after.Next = nil
+	before.Next = afterhead.Next
+	return beforehead.Next
+}

88. Merge Sorted Array.go

@@ -0,0 +1,21 @@
+package main
+
+func merge(nums1 []int, m int, nums2 []int, n int) {
+	for m > 0 || n > 0 {
+		if n == 0 {
+			break
+		}
+		if m == 0 {
+			nums1[n-1] = nums2[n-1]
+			n--
+			continue
+		}
+		if nums1[m-1] > nums2[n-1] {
+			nums1[m+n-1] = nums1[m-1]
+			m--
+		} else {
+			nums1[m+n-1] = nums2[n-1]
+			n--
+		}
+	}
+}