Answer:
b.used is 2, b.data[0] is 4, b.data[1] is 6
Explanation:
bag b;
b.insert(5); // b has 5
b.insert(4); // b has 5,4
b.insert(6); // b has 5,4,6
b.erase_one(5); // now 5 is removed , b has 4,6
so no:of elements b.used is 2
b[0]=4;
b[1]=6;
From hacking into public websites where you pay and stuff, or put in a fake official window to lure out your private info.
