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@grumpy : Thx for pointing out my mistake >.< i guess im a bit too careless =p
@smokeyangel : i will keep that in mind.

btw, if fflush would result in unportable code, my guess would be...

do{
....printf("Continue? (Y/N)");
fflush(stdin);
cont = toupper(getchar());
if ((cont!='Y') || (cont!='N')) {
printf("Invalid input! Continue? (Y/N) ");
fflush(stdin);...