Length of longest common subsequence containing vowels

// C# implementation to find the 
// length of longest common subsequence
// which contains all vowel characters
using System;

class GFG
{

// function to check whether 
// 'ch' is a vowel or not
static int isVowel(char ch) 
{
    if (ch == 'a' || ch == 'e' || 
        ch == 'i' || ch == 'o' ||
        ch == 'u')
        return 1;
    return 0;
}

// find max value
static int max(int a, int b)
{
    return (a > b) ? a : b;
}

// function to find the length of 
// longest common subsequence which
// contains all vowel characters
static int lcs(String X, String Y,
               int m, int n)
{
    int [,]L = new int[m + 1, n + 1];
    int i, j;

    // Following steps build L[m+1,n+1] 
    // in bottom up fashion. Note that 
    // L[i,j] contains length of LCS of
    // X[0..i-1] and Y[0..j-1]
    for (i = 0; i <= m; i++) 
    {
        for (j = 0; j <= n; j++) 
        {
            if (i == 0 || j == 0)
                L[i, j] = 0;

            else if ((X[i - 1] == Y[j - 1]) && 
                    isVowel(X[i - 1]) == 1)
                L[i, j] = L[i - 1, j - 1] + 1;
 
            else
                L[i, j] = max(L[i - 1, j],
                              L[i, j - 1]);
        }
    }

    // L[m,n] contains length of LCS 
    // for X[0..n-1] and Y[0..m-1]
    // which contains all vowel characters
    return L[m, n];
}

// Driver Code
static public void Main(String []args)
{
    String X = "aieef";
    String Y = "klaief";

    int m = X.Length;
    int n = Y.Length;

    Console.WriteLine("Length of LCS = " + 
                         lcs(X, Y, m, n));
}
}

// This code is contributed by Arnab Kundu

using System;

public class GFG {
    // Function to check whether 'ch' is a vowel or not
    static bool IsVowel(char ch) {
        if (ch == 'a' || ch == 'e' || ch == 'i' || ch == 'o' || ch == 'u')
            return true;
        return false;
    }

    // Function to find the length of longest common subsequence
    // which contains all vowel characters
    static int LCSWithVowels(char[] X, char[] Y, int m, int n) {
        // Initialize an array dp to store computations of subproblems
        int[] dp = new int[n + 1];

        // Iterating over subproblems to get the current value from previous computations
        for (int i = 1; i <= m; i++) {
            // To store just the previous value
            int prev = 0;
            for (int j = 1; j <= n; j++) {
                // Current value
                int curr = dp[j];
                if (X[i - 1] == Y[j - 1] && IsVowel(X[i - 1]))
                    dp[j] = prev + 1;
                else
                    dp[j] = Math.Max(dp[j], dp[j - 1]);

                // Assigning values to iterate further
                prev = curr;
            }
        }

        // Return the answer
        return dp[n];
    }

    // Driver Code
    static void Main(string[] args) {
        char[] X = "aieef".ToCharArray();
        char[] Y = "klaief".ToCharArray();

        int m = X.Length;
        int n = Y.Length;

        Console.WriteLine("Length of LCS = " + LCSWithVowels(X, Y, m, n));
    }
}