
def lps(str):
    n = len(str)
 
    # Create a table to store results of subproblems
    L = [[0 for x in range(n)] for x in range(n)]
 
    # Strings of length 1 are palindrome of length 1
    for i in range(n):
        L[i][i] = 1
 
    for cl in range(2, n+1):
        for i in range(n-cl+1):
            j = i+cl-1
            if str[i] == str[j] and cl == 2:
                L[i][j] = 2
            elif str[i] == str[j]:
                L[i][j] = L[i+1][j-1] + 2
            else:
                L[i][j] = max(L[i][j-1], L[i+1][j]);
 
    return L[0][n-1]


seq = "abcdeRTONUedcba"
lps_len = str(lps(seq))
print("Length of Longest palindromic subsequence is: " + lps_len)
