Merge pull request #61 from KongJHong/master

Add Solution 035[CPP]

Author: yanglbme

solution/035.Search Insert Position/README.md

@@ -38,6 +38,7 @@
 
 除此之外还可用二分法做解。
 
+
 ```java
 class Solution {
     public int searchInsert(int[] nums, int target) {
@@ -90,3 +91,87 @@ class Solution {
     }
 }
 ```
+
+#### CPP
+
+思路1：
+
+1. 先调函数查找是否存在target元素
+2. 若存在，用二分法进行查找，或者顺序遍历
+3. 若不存在，则顺序遍历插入
+
+时间复杂度O(log2(n))~O(n)
+
+思路2：
+ 1. 直接顺序遍历---需要点取巧，下标比nums长度小，nums[p]元素要比targat小
+
+ 时间复杂度O(n)
+
+```CPP
+class Solution {
+public:
+    int searchInsert(vector<int>& nums, int target) {
+        int len = nums.size();
+        if(len == 0){
+            nums.push_back(target);
+            return 0;
+        }
+
+        auto iter = find(nums.begin(),nums.end(),target);
+        
+        if(iter != nums.end()){
+           return binarySearch(nums,0,len - 1,target);
+        }
+        else{
+            int slow = 0;
+            int fast = 1;
+            
+            if(nums[0] >= target)return 0;
+            if(nums[len-1] <= target)return len;
+            
+            while(fast < len){
+                if(nums[slow] <= target && nums[fast] > target){
+                    nums.insert(nums.begin() + fast,target);
+                    return fast;
+                }
+                else{
+                    slow++;
+                    fast++;
+                }
+            }
+            return fast;
+        } 
+    }
+    
+    
+    int binarySearch(vector<int> &nums,int left,int right,int target){
+        if(nums[left] == target)return left;
+        if(nums[right] == target)return right;
+        
+        int mid = (left + right) / 2;
+        
+        if(nums[mid] > target)return binarySearch(nums,left+1,mid,target);
+        else if(nums[mid] < target)return binarySearch(nums,mid,right-1,target);
+        else return mid;
+    }
+    
+};
+
+-------------------------
+class Solution {
+public:
+    int searchInsert(vector<int>& nums, int target) {
+        if (nums.size() == 0) {
+            nums.push_back(target);
+            return 0;
+        }
+        unsigned int i = 0;
+        
+        while(i<nums.size()&&nums[i]<target)i++;
+
+        nums.insert(nums.begin() + i, target);
+        return i;
+    }
+};
+
+```

solution/035.Search Insert Position/Solution.cpp

@@ -0,0 +1,65 @@
+class Solution {
+public:
+    int searchInsert(vector<int>& nums, int target) {
+        int len = nums.size();
+        if(len == 0){
+            nums.push_back(target);
+            return 0;
+        }
+
+        auto iter = find(nums.begin(),nums.end(),target);
+        
+        if(iter != nums.end()){
+           return binarySearch(nums,0,len - 1,target);
+        }
+        else{
+            int slow = 0;
+            int fast = 1;
+            
+            if(nums[0] >= target)return 0;
+            if(nums[len-1] <= target)return len;
+            
+            while(fast < len){
+                if(nums[slow] <= target && nums[fast] > target){
+                    nums.insert(nums.begin() + fast,target);
+                    return fast;
+                }
+                else{
+                    slow++;
+                    fast++;
+                }
+            }
+            return fast;
+        } 
+    }
+    
+    
+    int binarySearch(vector<int> &nums,int left,int right,int target){
+        if(nums[left] == target)return left;
+        if(nums[right] == target)return right;
+        
+        int mid = (left + right) / 2;
+        
+        if(nums[mid] > target)return binarySearch(nums,left+1,mid,target);
+        else if(nums[mid] < target)return binarySearch(nums,mid,right-1,target);
+        else return mid;
+    }
+    
+};
+
+-------------------------
+class Solution {
+public:
+    int searchInsert(vector<int>& nums, int target) {
+        if (nums.size() == 0) {
+            nums.push_back(target);
+            return 0;
+        }
+        unsigned int i = 0;
+        
+        while(i<nums.size()&&nums[i]<target)i++;
+
+        nums.insert(nums.begin() + i, target);
+        return i;
+    }
+};