}
			}
		}
	}
}

func testSqr(t *testing.T, x nat) {
	got := make(nat, 2*len(x))
	want := make(nat, 2*len(x))
	got = got.sqr(x)
	want = want.mul(x, x)
	if got.cmp(want) != 0 {
		t.Errorf("basicSqr(%v), got %v, want %v", x, got, want)
	}
}

func TestSqr(t *testing.T) {
	for _, a := range prodNN {
		if a.x != nil {
			testSqr(t, a.x)
		}
		if a.y != nil {
			testSqr(t, a.y)