import java.io.*;
import java.util.*;

public class Main {
    static PrintWriter pw;
    static Scanner sc;
    static long ceildiv(long x, long y) { return (x+y-1)/y; }
    static int mod(long x, int m) { return (int)((x%m+m)%m); }
    static void put(HashMap<Integer, Integer> map, Integer p){if(map.containsKey(p)) map.replace(p, map.get(p)+1); else map.put(p, 1); }
    static void rem(TreeMap<Integer, Integer> map, Integer p){ if(map.get(p)==1) map.remove(p);else map.replace(p, map.get(p)-1); }
    static void printf(double x, int dig){ String s="%."+dig+"f"; pw.printf(s, x); }
    static int Int(boolean x){ return x?1:0; }
    static final int inf=(int)1e9, mod=998244353;
    static final long infL=inf*1l*inf;
    static final double eps=1e-9;
    public static long gcd(long x, long y) { return y==0? x: gcd(y, x%y); }
    public static void main(String[] args) throws Exception{
        sc=new Scanner(System.in);
        pw=new PrintWriter(System.out);
        int t=sc.nextInt();
        while(t-->0)
            testcase();
        pw.close();
    }
    static void testcase() throws IOException{
        int n=sc.nextInt(), m=sc.nextInt(), arr[]=sc.nextArr(n);
        long sum=0;
        for (int i = 0; i < n; i++)
            sum+=arr[i];
        Stack<LP> st=new Stack<>();
        sum=0;
        for (int i = 0; i < n; i++) {
            sum+=arr[i];
            LP temp=new LP(sum, i);
            if(st.isEmpty() || st.peek().x<sum)
                st.add(temp);
        }
        LP[] min=new LP[st.size()];
        for (int i = 0; i < min.length; i++)
            min[i]=st.pop();
        reverse(min);
//        for (int i = 0; i < min.length; i++)
//            pw.println(min[i].x+" "+min[i].y);
//        pw.flush();
        while(m-->0)
            solve(sum, min, sc.nextInt(), n);
        pw.println();
    }
    static void solve(long sum, LP[] min, int x, int len){
        int n=min.length;
        long need=x-min[n-1].x;
        long ans=0;
        if(need>0){
            if(sum<=0){
                pw.print("-1 ");
                return;
            }
            long d=ceildiv(need, sum);
            ans+=d*len;
            need=x-sum*d;
        }else{
            need=x;
        }
        int st=0, end=n-1;
        int ans2=len;
        while(st<=end){
            int mid=(st+end)/2;
            if(min[mid].x>=need){
                ans2=(int) min[mid].y+1;
                end=mid-1;
            }else{
                st=mid+1;
            }
        }
        pw.print(ans+ans2-1+" ");
    }
    static void reverse(LP[] arr){
        for (int i = 0; i < arr.length/2; i++) {
            LP temp=arr[i];
            arr[i]=arr[arr.length-1-i];
            arr[arr.length-1-i]=temp;
        }
    }
    static int test(int x, HashMap<Integer, Integer> map){
        int ans=0;
        for (Map.Entry<Integer, Integer> a: map.entrySet())
            ans+=a.getValue() >= x? a.getValue()-x: a.getValue();
        return ans;
    }
    static void printArr(int[] arr) {
        for (int i = 0; i < arr.length; i++)
            pw.print(arr[i] + " ");
        pw.println();
    }
    static void printArr(long[] arr) {
        for (int i = 0; i < arr.length; i++)
            pw.print(arr[i] + " ");
        pw.println();
    }
    static void printArr(double[] arr) {
        for (int i = 0; i < arr.length; i++)
            pw.print(arr[i] + " ");
        pw.println();
    }
    static void printArr(Integer[] arr) {
        for (int i = 0; i < arr.length; i++)
            pw.print(arr[i] + " ");
        pw.println();
    }
    static void printArr(ArrayList list) {
        for (int i = 0; i < list.size(); i++)
            pw.print(list.get(i)+" ");
        pw.println();
    }
    static void printArr(boolean[] arr) {
        StringBuilder sb=new StringBuilder();
        for(boolean b: arr)
            sb.append(Int(b));
        pw.println(sb);
    }
    static class Scanner {
        StringTokenizer st;
        BufferedReader br;
        public Scanner(InputStream s) {
            br = new BufferedReader(new InputStreamReader(s));
        }

        public Scanner(FileReader r) {
            br = new BufferedReader(r);
        }

        public String next() throws IOException {
            while (st == null || !st.hasMoreTokens())
                st = new StringTokenizer(br.readLine());
            return st.nextToken();
        }

        public int nextInt() throws IOException {
            return Integer.parseInt(next());
        }

        public long nextLong() throws IOException {
            return Long.parseLong(next());
        }

        public String nextLine() throws IOException {
            return br.readLine();
        }

        public double nextDouble() throws IOException {
            return Double.parseDouble(next());
        }
        public int[] nextDigits() throws IOException{
            String s=nextLine();
            int[] arr=new int[s.length()];
            for(int i=0; i<arr.length; i++)
                arr[i]=s.charAt(i)-'0';
            return arr;
        }
        public int[] nextArr(int n) throws IOException {
            int[] arr = new int[n];
            for (int i = 0; i < arr.length; i++)
                arr[i] = nextInt();
            return arr;
        }
        public Integer[] nextsort(int n) throws IOException{
            Integer[] arr=new Integer[n];
            for(int i=0; i<n; i++)
                arr[i]=nextInt();
            return arr;
        }
        public Pair nextPair() throws IOException{
            return new Pair(nextInt(), nextInt());
        }
        public long[] nextLongArr(int n) throws IOException{
            long[] arr=new long[n];
            for (int i = 0; i < n; i++)
                arr[i]=sc.nextLong();
            return arr;
        }
        public Pair[] nextPairArr(int n) throws IOException{
            Pair[] arr=new Pair[n];
            for(int i=0; i<n; i++)
                arr[i]=nextPair();
            return arr;
        }
        public boolean ready() throws IOException {
            return br.ready();
        }
    }
    static class Pair implements Comparable<Pair>{
        int x;
        int y;
        public Pair(int x, int y) {
            this.x=x;
            this.y=y;
        }
        public boolean contains(int a){
            return x==a || y==a;
        }
        public int hashCode() {
            return (this.x*1000000000+this.y);
        }
        public int compareTo(Pair p){
            if(x==p.x)
                return y-p.y;
            return x-p.x;
        }
        public boolean equals(Object obj) {
            if (obj == null) {
                return false;
            }
            if (this.getClass() != obj.getClass()) {
                return false;
            }
            Pair p = (Pair) obj;
            return this.x==p.x && this.y==p.y;
        }
        public Pair clone(){
            return new Pair(x, y);
        }
        public String toString(){
            return this.x+" "+this.y;
        }
        public void add(Pair p){
            x+=p.x;
            y+=p.y;
        }
        public Pair negative(){
            return new Pair(-x, -y);
        }
    }
    static class LP implements Comparable<LP>{
        long x, y;
        public LP(long a, long b){
            x=a;
            y=b;
        }
        public void add(LP p){
            x+=p.x;
            y+=p.y;
        }
        public boolean equals(LP p){
            return p.x==x && y==p.y;
        }
        public String toString(){
            return this.x+" "+this.y;
        }
        public int compareTo(LP p){
            int a=Long.compare(x, p.x);
            if(a!=0)
                return a;
            return Long.compare(y, p.y);
        }
    }
}