import sys # sys.setrecursionlimit(200005) # sys.set_int_max_str_digits(200005) int1 = lambda x: int(x)-1 pDB = lambda *x: print(*x, end="\n", file=sys.stderr) p2D = lambda x: print(*x, sep="\n", end="\n\n", file=sys.stderr) def II(): return int(sys.stdin.readline()) def LI(): return list(map(int, sys.stdin.readline().split())) def LLI(rows_number): return [LI() for _ in range(rows_number)] def LI1(): return list(map(int1, sys.stdin.readline().split())) def LLI1(rows_number): return [LI1() for _ in range(rows_number)] def SI(): return sys.stdin.readline().rstrip() dij = [(0, 1), (-1, 0), (0, -1), (1, 0)] # dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)] # inf = -1-(-1 << 31) inf = -1-(-1 << 62) # md = 10**9+7 md = 998244353 from bisect import bisect_left tri=lambda x:x*(x+1)//2 lim=10**9 c=[0] t=[0] n,q=LI() aa=LI() for a in aa: c.append(c[-1]+a) t.append(t[-1]+tri(a)) if t[-1]>lim:break def binary_search(l, r, minimize): if minimize: l -= 1 else: r += 1 while l+1 < r: m = (l+r)//2 if ok(m) ^ minimize: l = m else: r = m if minimize: return r return l def ok(m): return t[i]+tri(m)>=s for _ in range(q): s=II() i=bisect_left(t,s)-1 if i>=n: print(-1) else: print(c[i]+binary_search(1,aa[i],True))