K-Ordered LCS by DP

#1

Can’t Understand the recursive approach!

#2

@Codemaniac_Aditya think this way, let’s say you are at index i and j of array1 and array2 respetively along with K allowed changes in array1, now there are two possibilities:

  1. arr1[i]==arr2[j], here you simply return 1+K_lcs(i+1,j+1,K)
  2. arr1[i]!=arr2[j], now you can move either of index , also if K>0 then you can also make arr[i] equal to arr[j], hence you do it as:
    return max(K_lcs(i+1,j,K), K_lcs(i,j+1,K), K_lcs(i+1,j+1,K-1)
#3

return max(K_lcs(i+1,j,K), K_lcs(i,j+1,K), 1 + K_lcs(i+1,j+1,K-1) is correct for 2.

#4

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