'''

You are given a DNA sequence: a string consisting of characters A, C, G, and T. Your task is to find the longest repetition in the sequence. This is a maximum-length substring containing only one type of character.

'''

# This function mainly returns LCS(str, str)

# with a condition that same characters at

# same index are not considered.

def findLongestRepeatingSubSeq( str):

n = len(str)

# Create and initialize DP table

dp=[[0]*(n+1)]*(n+1)

# Fill dp table (similar to LCS loops)

for i in range(1,n+1):

for j in range(1,n+1):

# If characters match and indexes are

# not same

if (str[i-1] == str[j-1] and i != j):

dp[i][j] = 1 + dp[i-1][j-1]

# If characters do not match

else:

dp[i][j] = max(dp[i][j-1], dp[i-1][j])

return dp[n][n]

# Driver Program

if __name__=='__main__':

str = input()

print("The length of the largest subsequence that repeats itself is : "

,findLongestRepeatingSubSeq(str))

# this code is contributed by Amit Agarwal