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

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        int n = sc.nextInt();
        int q = sc.nextInt();
        Unit.values = new int[n];
        for (int i = 0; i < n; i++) {
            Unit.values[i] = sc.nextInt();
        }
        Unit[] units = new Unit[n];
        int current = 0;
        for (int i = 0; i < n; i++) {
            units[i] = new Unit(current, i + 1);
            current = units[i].last;
        }
        StringBuilder sb = new StringBuilder();
        while (q-- > 0) {
            int x = sc.nextInt();
            if (x > units[n - 1].last) {
                sb.append("-1\n");
                continue;
            }
            int ans = 0;
            for (int i = 0; i < n; i++) {
                if (x <= units[i].last) {
                    ans += units[i].getIdx(x);
                    break;
                } else {
                    ans += units[i].count;
                }
            }
            sb.append(ans).append("\n");
        }
        System.out.print(sb);
    }
    
    static class Unit {
        static int[] values;
        int start;
        int count;
        int last;
        
        public Unit(int start, int count) {
            this.start = start;
            this.count = count;
            last = start;
            for (int i = 0; i < count; i++) {
                last += values[i];
            }
        }
        
        public int getIdx(int x) {
            x -= start;
            for (int i = 0; i < count; i++) {
                x -= values[i];
                if (x <= 0) {
                    return i + 1;
                }
            }
            return -1;
        }
    }
    
    static int getGCD(int x, int y) {
        if (y == 0) {
            return x;
        } else {
            return getGCD(y, x % y);
        }
    }
}
class Utilities {
    static String arrayToLineString(Object[] arr) {
        return Arrays.stream(arr).map(x -> x.toString()).collect(Collectors.joining("\n"));
    }
    
    static String arrayToLineString(int[] arr) {
        return String.join("\n", Arrays.stream(arr).mapToObj(String::valueOf).toArray(String[]::new));
    }
}
class Scanner {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer("");
    StringBuilder sb = new StringBuilder();
    
    public Scanner() throws Exception {
        
    }
    
    public int nextInt() throws Exception {
        return Integer.parseInt(next());
    }
    
    public long nextLong() throws Exception {
        return Long.parseLong(next());
    }
    
    public double nextDouble() throws Exception {
        return Double.parseDouble(next());
    }
    
    public int[] nextIntArray() throws Exception {
        return Stream.of(br.readLine().split(" ")).mapToInt(Integer::parseInt).toArray();
    }
    
    public String next() throws Exception {
        while (!st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }
    
}