import java.io.PrintWriter

fun main() {
    val (n, q) = readln().split(" ").map { it.toInt() }
    val a = readln().split(" ").map { it.toInt() }
    val s = Array(q) {
        readln().toInt()
    }

    val pList = (0 until n).map { it -> (1..a[it]).toList().let {P(it.size, it.sum().toLong(), it.toIntArray()) } }
    val wholeSum = pList.sumOf { it.sum }

    val out = PrintWriter(System.out)
    for(i in 0 until q) {
        if(s[i] > wholeSum) {
            out.println(-1)
            continue
        }

        var sum = 0L
        var sizeSum = 0
        for(j in pList.indices) {
            val p = pList[j]

            sizeSum += p.size
            sum += p.sum

            if(sum == s[i].toLong()) {
                out.println(sizeSum)
                break
            } else if(sum > s[i]) {
                sizeSum -= p.size
                sum -= p.sum

                out.println(s[i] - sum + sizeSum)
                break
            }
        }
    }

    out.flush()
}

data class P(
    val size: Int,
    val sum: Long,
    val value: IntArray,
)