package Yukicoder

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 readLineDouble() : Double {
        val str = readLine() as String
        return str.toDouble()
    }


//    fun readLineStringArray(): List<String> {
//        val str = readLine() as String
//        val arrStr = str.split(" ")
//        return arrStr
//    }

    val num = readLineInt()
    val arrInt = readLineIntArray()

    var count = 0
    var tmpCount = 0
    var tmp = Integer.MIN_VALUE

    for (item in arrInt) {
        if (tmpCount != item) {
            if (tmpCount == 1) {
                count++
            }
            tmpCount = 1
            tmp = item
        } else {
            tmpCount++
        }
    }
    if (tmpCount == 1)
        count++
    println(count)

}