import java.util.*

fun main(args: Array<String>) {
    var list = IO.readIntList()
    var ans = list[2] - (list[0] - list[1])
    ans = if (ans < 0) 0 else ans
    println(ans)
}

object IO {
    fun readInt(): Int {
        return readLine()!!.toInt()
    }
    fun readIntList(): List<Int> {
        return readLine()!!.split(" ").map(String::toInt)
    }
}