s=input()
n=len(s)
out=1
for i in range(n):
	for j in range(i+1,n):
		if i==0 and j==n-1:continue
		h=1
		st,t=i,j
		while t-st>0:
			if s[st]!=s[t]:h=0
			st+=1
			t-=1
		if h:out=max(out,j-i+1)
print(out)