Create 14_longest_common_prefix.cpp

Author: Rashed112

solutions/14_longest_common_prefix.cpp

@@ -0,0 +1,44 @@
+//Solution-1: Brute Force Approach
+//Time: O(N^2)
+//Space: O(N)
+
+class Solution {
+public:
+    string longestCommonPrefix(vector<string>& strs) {
+        int n=strs.size();
+        string res = "";
+        sort(strs.begin(), strs.end());
+        string longString = strs[n-1];
+        for(int t=0; t<longString.size();t++){
+            char temp = longString[t]; 
+            for(int i=0;i<strs.size();i++){
+                if(strs[i][t] != temp){
+                    return res;
+                }
+            }
+            res+=temp;
+        }
+        return res;
+    }
+};
+
+//Solution-2: Optimal Approach
+//Time: O(N*logN)
+//Space: O(N)
+
+class Solution {
+public:
+    string longestCommonPrefix(vector<string>& strs) {
+        int n=strs.size();
+        string res = "";
+        sort(strs.begin(), strs.end());
+        string smallString = strs[0], largeString = strs[n-1];
+        for(int i=0; i<smallString.size();i++){
+            if(smallString[i] != largeString[i]){
+                return res;
+            }
+            res+=smallString[i];
+        }
+        return res;
+    }
+};