Merge pull request manishbisht#55 from Rajdeep-G/master

Added Least Common Subsequence using Dp

Author: manishbisht

Algorithms/Dynamic Programming/LCS_DP.cpp

@@ -0,0 +1,63 @@
+//Length of Longest Common Subsequence problem using Dynamic Programming
+
+
+#include<iostream>
+#include<string.h>
+using namespace std; 
+  
+/* Function to get max of 2 integers */
+int max(int a, int b)  
+{  
+    return (a > b)? a : b;  
+}  
+  
+
+int longestCommonSubsequence( char *arr1, char *arr2, int m, int n )  
+{  
+    int LCS[m + 1][n + 1];  
+    int i, j;  
+      
+    /* In the following steps LCS[i][j]  
+       contains length of Longest common subsequence of arr1[0..i-1] 
+       and arr2[0..j-1]. It uses a Dynamic programming approach */
+    for (i = 0; i <= m; i++)  
+    {  
+        for (j = 0; j <= n; j++)  
+        {  
+        if (i == 0 || j == 0)  
+            LCS[i][j] = 0;  
+      
+        else if (arr1[i - 1] == arr2[j - 1])  
+            LCS[i][j] = LCS[i - 1][j - 1] + 1;  
+      
+        else
+            LCS[i][j] = max(LCS[i - 1][j], LCS[i][j - 1]);  
+        }  
+    }  
+          
+    //Returns the longest common subsequence
+    return LCS[m][n];  
+}  
+  
+
+  
+//Main Function
+int main()  
+{  
+    char arr1[100];  
+    char arr2[100];  
+
+    cout<<"\nEnter the 1st string: ";
+    cin>>arr1;
+
+    cout<<"\nEnter the 2nd string: ";
+    cin>>arr2;
+      
+    int s1 = strlen(arr1);  
+    int s2 = strlen(arr2);  
+      
+    cout << "\nLength of the Longest Common Subsequence is: " 
+         << longestCommonSubsequence( arr1, arr2, s1, s2 )<<endl;  
+      
+    return 0;  
+}