/* -*- coding: utf-8 -*- * * 2560.cc: No.2560 A_1 < A_2 < ... < A_N - yukicoder */ #include #include using namespace std; /* constant */ const int MAX_N = 200000; /* typedef */ typedef long long ll; /* global variables */ /* subroutines */ /* main */ int main() { int tn; scanf("%d", &tn); while (tn--) { int n; ll x; scanf("%d%lld", &n, &x); if ((ll)n * (n + 1) / 2 > x) { puts("-1"); continue; } for (int i = 1; i < n; i++) printf("%d ", i); printf("%lld\n", x - (ll)n * (n - 1) / 2); } return 0; }