Merge pull request #199 from RAUNAK-PANDEY/raunak

Shortest common supersequence in C++

Author: arnab2001

Dynamic Programming/ShortestCommonSupersequence.cpp

@@ -0,0 +1,80 @@
+
+/*
+Given two strings X and Y of lengths m and n respectively, find the length of the smallest string which has both, X and Y as its sub-sequences.
+Note: X and Y can have both uppercase and lowercase letters.
+
+Example 1
+
+Input:
+X = abcd, Y = xycd
+Output: 6
+Explanation: Shortest Common Supersequence
+would be abxycd which is of length 6 and
+has both the strings as its subsequences.
+Example 2
+
+Input:
+X = efgh, Y = jghi
+Output: 6
+Explanation: Shortest Common Supersequence
+would be ejfghi which is of length 6 and
+has both the strings as its subsequences.
+*/
+  
+
+#include<bits/stdc++.h>
+using namespace std;
+
+ 
+class Solution
+{
+    public:
+    
+    int LCS(string X, string Y, int m, int n){
+        int dp[m+1][n+1];
+        memset(dp,-1,sizeof(dp));
+        for(int i=0;i<m+1;i++)
+        {
+            for(int j=0;j<n+1;j++)
+            {
+                if(i==0 || j==0) dp[i][j]=0;
+                else if(X[i-1] == Y[j-1]){
+                    dp[i][j] = 1+dp[i-1][j-1];
+                }
+                else{
+                    dp[i][j] = max(dp[i-1][j] , dp[i][j-1]);
+                }
+            }
+        }
+        return dp[m][n];
+    }
+    int shortestCommonSupersequence(string X, string Y, int m, int n)
+    {
+        //code here
+         
+         
+        return (m + n) - LCS(X, Y , m , n);
+    }
+};
+
+ 
+
+int main()
+{   
+    
+    int t;
+    
+    //taking total testcases
+    cin >> t;
+    while(t--){
+    string X, Y;
+    //taking String X and Y
+	cin >> X >> Y;
+	
+	//calling function shortestCommonSupersequence()
+	Solution obj;
+	cout << obj.shortestCommonSupersequence(X, Y, X.size(), Y.size())<< endl;
+    }
+	return 0;
+}
+