a,b=map(float, input().split())
if a!=0:
print(f"-b/a:.1f")
else:
if b==0:
print("Vo_so_nghiem")
else:
print("Vo_nghiem")
YSxiPW1hcChmbG9hdCwgaW5wdXQoKS5zcGxpdCgpKQppZiBhIT0wOgogcHJpbnQoZiItYi9hOi4xZiIpCmVsc2U6CiBpZiBiPT0wOgogIHByaW50KCJWb19zb19uZ2hpZW0iKQogZWxzZToKICBwcmludCgiVm9fbmdoaWVtIik=