For the first one, if you only want to announce once, then add the announce like below:
for(set @i,@i+1; getarg(@i)!=0; set @i,@i+2) getitem getarg(@i),getarg(@i+1);
announce "Yay, the player got items",bc_all;
If you want it to announce for each item, change the for loop like this: (to make sure it does both commands for each loop)
for(set @i,@i+1; getarg(@i)!=0; set @i,@i+2){
getitem getarg(@i),getarg(@i+1);
announce "Yay, the player got another item",bc_all;
}
For the second one, you can add an announce, like I did in the first example, after the line which gives the item:
getitem $CB_Prize[.@d], $CB_Prize[.@d+3];
// Add announce here