ahmed: I dont know how to do that with an integer but if you take input in character form and the use the various functions of ctype.h like isdigit(),isalpha() etc you can check for integer or character input.

cwk9:
>>All you c++ gurus can feel free to make fun of my crappy coding ability.
dont flame me you asked fo it

>>while (loop = 0)
this should be -> while(loop==0)

>>if (age > 21) {loop = 1;}
if there is just 1 statement in the loop there's no need for putting "{" and "}"

>>loop=o;
this should be -> loop=0;