so bitcoin is very hard to attack in this method. (51%)
where did this figure come from, 51%? What kind of method?
Please enlight me.
...
Bought account, or just didn't bother to learn the basics?
so bitcoin is very hard to attack in this method. (51%)
but other cryptocurrencies are very vulnurable to such attacks.
so attacker can steal other currencies and then buy with them bitcoins...
how can this problem be solved?
I honestly see no problem here. I would in fact argue whether doing such thing is illegal (iirc Bitcoin core dev, Luke jr performed 51% attack on some SHA256 altcoin in the past). But the bottom line is, if someone is willing to exchange their bitcoins for some vulnerable shitcoin, then it's their choice (and their loss).