Question

ques in c program
difference b/w ++i and i++

Answer 1

++i:
int i = 5;
printf("%d", ++i); //i = 6

i++:
int i = 5;
printf("%d", i++); //i = 5

++i increments the integer before its put into the outstream whereas i++ increments the integer after its printed

Answer 2

++i is called autopreincrement. i is incremented before it's evaluated.
i++ is called autopostincrement. i is evaluated and then incremented.

IAMGERMAN's code demonstrates this.

BTW, there's also autopre/postdecrement too.