Create Longest_Common_Subsequence.c

Author: santhosh-programmer

Dynamic-Programming/Longest_Common_Subsequence.c

@@ -0,0 +1,40 @@
+// Given two strings find the length of the common longest subsequence(need not be contiguous) between the two.
+
+// Example:
+
+//  s1: ggtabe
+
+//  s2: tgatasb
+ 
+//  The length is 4
+
+
+#include<stdio.h>
+#include<string.h>
+int n,m,t1,t2;
+int find(char s1[],char s2[],int i,int j,int ans[][m])
+{
+    if(i==n||j==m)
+        return 0;
+    else if(s1[i]==s2[j])
+        return ans[i][j]=1+find(s1,s2,i+1,j+1,ans);
+    else if(ans[i][j]!=0)
+        return ans[i][j];
+    t1=find(s1,s2,i+1,j,ans);
+    t2=find(s1,s2,i,j+1,ans);
+    ans[i][j]=(t1>t2)?t1:t2;
+    return ans[i][j];
+}
+int main()
+{
+    char s1[10],s2[10];
+    scanf("%s%s",s1,s2);
+    n=strlen(s1),m=strlen(s2);
+    int ans[n][m];
+    for(int i=0;i<n;i++)
+    {
+        for(int j=0;j<m;j++)
+        ans[i][j]=0;
+    }
+    printf("%d",find(s1,s2,0,0,ans));
+}