package Yukicoder

/**
 * Created by hichikawa on 2015/11/12.
 */
fun main(args: Array<String>) {
    fun readLineLongArray(): List<Long> {
        val str = readLine() as String
        val arrStr = str.split(" ")
        val ret = arrStr.map { it.toLong() }
        return ret
    }

    fun readLineLong(): Long {
        val str = readLine() as String
        return str.toLong()
    }

    fun readLineInt(): Int {
        val str = readLine() as String
        return str.toInt()
    }

    fun readLineIntArray() : List<Int> {
        val str = readLine() as String
        val arrStr = str.split(" ")
        val ret = arrStr.map { it.toInt() }
        return ret
    }

    fun readLineDoubleArray(): List<Double> {
        val str = readLine() as String
        val arrStr = str.split(" ")
        val ret = arrStr.map { it.toDouble() }
        return ret
    }

    fun checkKai(str : String , startIndex : Int, endIndex : Int) : Boolean{
        for (i in 0..((endIndex-startIndex)/2)) {
            if (str.get(startIndex+i) != str.get(endIndex-i)) {
                return false
            }
        }
        return true
    }

    val inputStr = readLine() as String
    var maxI = Int.MIN_VALUE
    for ((i, ch) in inputStr.withIndex()) {
//    var lastIndex = inputStr.length
        var lastIndex = if (i != 0) inputStr.length else inputStr.length-1
        do {
            lastIndex = inputStr.lastIndexOf(inputStr[i], lastIndex-1)
            if (checkKai(inputStr, i, lastIndex)) {
//                println((lastIndex-i).toString() + " " + i + " " + lastIndex)
                if (maxI <= (lastIndex-i)) {
                    maxI = lastIndex-i+1
                }
                break
            }
        } while (i < lastIndex)
    }
    println(maxI)
}