“LegestpalindromicsUbSequence (DP)” Code-Antworten

LegestpalindromicsUbSequence (DP)

// C++ program of above approach
#include<bits/stdc++.h>
using namespace std;
 
// A utility function to get max of two integers
int max (int x, int y) { return (x > y)? x : y; }
 
// Returns the length of the longest palindromic subsequence in seq
int lps(char *seq, int i, int j)
{
// Base Case 1: If there is only 1 character
if (i == j)
    return 1;
 
// Base Case 2: If there are only 2
// characters and both are same
if (seq[i] == seq[j] && i + 1 == j)
    return 2;
 
// If the first and last characters match
if (seq[i] == seq[j])
    return lps (seq, i+1, j-1) + 2;
 
// If the first and last characters do not match
return max( lps(seq, i, j-1), lps(seq, i+1, j) );
}
 
/* Driver program to test above functions */
int main()
{
    char seq[] = "GEEKSFORGEEKS";
    int n = strlen(seq);
    cout << "The length of the LPS is "
         << lps(seq, 0, n-1);
    return 0;
}
 
// This code is contributed
// by Akanksha Rai