import kotlin.system.measureTimeMillis

fun main(args:Array<String>) {
    val columnCount = readLine()!!.toInt()
    val map = readLine()!!.split(" ").map { it.toInt()}.toMutableList()
    val total = map.sum()

    var fixColumnCount = 1
    var subTotal = 1
    var fixMap = mutableListOf(1)
    while (subTotal + (fixColumnCount + 2) <= total) {
        fixColumnCount += 2
        subTotal += fixColumnCount
        fixMap = fixMap.map { it + 1 }.toMutableList()
        fixMap.add(0, 1)
        fixMap.add(1)
    }

    map.addAll((1..fixColumnCount - 1).map { 0 })

    var pool = 0
    var count = 0
    for(i in (0 until fixMap.size)) {
        val num1 = fixMap[i]
        var num2 = map[i]
        var diff = num1 - num2
        if(Math.abs(diff) > Math.abs(pool) &&  diff * pool < 0) {
            count += Math.abs(diff) - Math.abs(pool)
        } else if(diff * pool >= 0) {
            count += Math.abs(diff)
        }
        pool += diff
    }
    println(count)
}