class SegmentTree: def __init__(self, init_val, segfunc, ide_ele): n = len(init_val) self.segfunc = segfunc self.ide_ele = ide_ele self.num = 1 << (n - 1).bit_length() self.tree = [ide_ele] * 2 * self.num self.size = n for i in range(n): self.tree[self.num + i] = init_val[i] for i in range(self.num - 1, 0, -1): self.tree[i] = self.segfunc(self.tree[2 * i], self.tree[2 * i + 1]) def update(self, k, x): k += self.num self.tree[k] = x while k > 1: k >>= 1 self.tree[k] = self.segfunc(self.tree[2*k], self.tree[2*k+1]) def query(self, l, r): if r==self.size: r = self.num res = self.ide_ele l += self.num r += self.num right = [] while l < r: if l & 1: res = self.segfunc(res, self.tree[l]) l += 1 if r & 1: right.append(self.tree[r-1]) l >>= 1 r >>= 1 for e in right[::-1]: res = self.segfunc(res,e) return res def bisect(self,l,r,x): if r==self.size: r = self.num l += self.num r += self.num segment = [] segment_r = [] while l>= 1 r >>= 1 segment += segment_r[::-1] tmp = self.ide_ele for pos in segment: check = self.segfunc(tmp,self.tree[pos]) if check > x: break else: tmp = check else: return -1 while pos < self.num: check = self.segfunc(tmp,self.tree[2*pos]) if check > x: pos = 2 * pos else: tmp = check pos = 2 * pos + 1 return pos - self.num import sys,random,bisect from collections import deque,defaultdict from heapq import heapify,heappop,heappush from itertools import permutations from math import log,gcd input = lambda :sys.stdin.readline().rstrip() mi = lambda :map(int,input().split()) li = lambda :list(mi()) N,M = mi() A = li() P = li() pos = [-1] * (N+1) for i in range(N): pos[P[i]] = i dp = [[False for j in range(M+1)] for i in range(N+1)] dp[N][0] = True for i in range(N)[::-1]: for j in range(M+1): if A[i] <= j: dp[i][j] = dp[i+1][j]|dp[i+1][j-A[i]] else: dp[i][j] = dp[i+1][j] if not dp[0][M]: exit(print(-1)) res = [] L = 0 S = 0 use = [False] * (N+1) while True: for i in range(1,N+1): tmp_L = max(L,pos[i]+1) tmp_rest = M - S - A[pos[i]] if 0 <= tmp_rest and not use[i] and L <= pos[i] and dp[tmp_L][tmp_rest]: res.append(i) L = max(L,pos[i]+1) S = S + A[pos[i]] use[i] = True break else: pass else: break print(len(res)) print(*[pos[i]+1 for i in res])