Create LongestCommonSubstring.java

Author: mohitsingla123

Longest Common Subsequence/LongestCommonSubstring.java

@@ -0,0 +1,51 @@
+// Calculate the lenght of longest Common substring
+//Solution:
+
+public class LongestCommonSubstring{
+
+     public static void main(String []args){
+        String a = "abcde";
+        String b = "abfce";
+        int i,j;
+        int lena = a.length();
+        int lenb = b.length();
+        int[][] arr = new int[lena+ 1][lenb+1];
+        
+        for(i = 0; i<= lena; i++ )
+        {
+            for(j = 0;j<=lenb; j++)
+            {
+                if(i==0 || j==0)
+                arr[i][j] = 0;
+            }
+        }
+        for(i = 1; i<= lena; i++ )
+        {
+            for(j = 1;j<=lenb; j++)
+            {
+                if(a.charAt(i-1) == b.charAt(j-1))
+                {
+                    arr[i][j] = 1 + arr[i-1][j-1];
+                }
+                else
+                arr[i][j] = 0;
+            }
+        }    
+        int max =0;
+        for(i = 0; i<= lena; i++ )
+        {
+            for(j = 0;j<=lenb; j++)
+            {
+                 if(i==j)
+                 {
+                     if(arr[i][j]>max)
+                     {
+                         max = arr[i][j];
+                     }
+                 }
+            }
+        }
+        
+        System.out.println("Longest Common Substring : "+max+" length");
+    }
+}