New Problem Solution - "1881. Maximum Value after Insertion"

Author: haoel

Diff for: README.md

@@ -9,7 +9,7 @@ LeetCode
 
 | # | Title | Solution | Difficulty |
 |---| ----- | -------- | ---------- |
-|1880|[Check if Word Equals Summation of Two Words](https://leetcode.com/problems/check-if-word-equals-summation-of-two-words/) | [C++](./algorithms/cpp/checkIfWordEqualsSummationOfTwoWords/CheckIfWordEqualsSummationOfTwoWords.cpp)|Easy|
+|1881|[Maximum Value after Insertion](https://leetcode.com/problems/maximum-value-after-insertion/) | [C++](./algorithms/cpp/maximumValueAfterInsertion/MaximumValueAfterInsertion.cpp)|Medium|
 |1871|[Jump Game VII](https://leetcode.com/problems/jump-game-vii/) | [C++](./algorithms/cpp/jumpGame/jumpGame.VII.cpp)|Medium|
 |1870|[Minimum Speed to Arrive on Time](https://leetcode.com/problems/minimum-speed-to-arrive-on-time/) | [C++](./algorithms/cpp/minimumSpeedToArriveOnTime/MinimumSpeedToArriveOnTime.cpp)|Medium|
 |1869|[Longer Contiguous Segments of Ones than Zeros](https://leetcode.com/problems/longer-contiguous-segments-of-ones-than-zeros/) | [C++](./algorithms/cpp/longerContiguousSegmentsOfOnesThanZeros/LongerContiguousSegmentsOfOnesThanZeros.cpp)|Easy|

Diff for: algorithms/cpp/maximumValueAfterInsertion/MaximumValueAfterInsertion.cpp

@@ -0,0 +1,59 @@
+// Source : https://leetcode.com/problems/maximum-value-after-insertion/
+// Author : Hao Chen
+// Date   : 2021-05-30
+
+/***************************************************************************************************** 
+ *
+ * You are given a very large integer n, represented as a string, and an integer digit x. The 
+ * digits in n and the digit x are in the inclusive range [1, 9], and n may represent a negative 
+ * number.
+ * 
+ * You want to maximize n's numerical value by inserting x anywhere in the decimal representation of n
+ * . You cannot insert x to the left of the negative sign.
+ * 
+ * 	For example, if n = 73 and x = 6, it would be best to insert it between 7 and 3, making n =  763.
+ * 	If n = -55 and x = 2, it would be best to insert it before the first 5, making n = -255.
+ * 
+ * Return a string representing the maximum value of n after the insertion.
+ * 
+ * Example 1:
+ * 
+ * Input: n = "99", x = 9
+ * Output: "999"
+ * Explanation: The result is the same regardless of where you insert 9.
+ * 
+ * Example 2:
+ * 
+ * Input: n = "-13", x = 2
+ * Output: "-123"
+ * Explanation: You can make n one of {-213, -123, -132}, and the largest of those three is -123.
+ * 
+ * Constraints:
+ * 
+ * 	1 <= n.length <= 10^5
+ * 	1 <= x <= 9
+ * 	The digits in n are in the range [1, 9].
+ * 	n is a valid representation of an integer.
+ * 	In the case of a negative n, it will begin with '-'.
+ ******************************************************************************************************/
+
+class Solution {
+public:
+    string maxValue(string n, int x) {
+        bool neg = false;
+        if (n[0] == '-') neg = true;
+        
+        int i;
+        
+        for( i=neg?1:0; i<n.size(); i++){
+            if (neg == true) {
+                if ( n[i]-'0' > x) break;
+            }else{ 
+                if (n[i]-'0' < x) break; 
+            }
+        }
+     
+        n.insert(n.begin()+i, x+'0');
+        return n;
+    }
+};