++i will give result i=i+1. If i=10 then in k = (++i)+(++i);
expression (++i) will give incremented value that means first increment will happen but in case of i++ the increment will be affected on i after the expression.
So i=10
k = (i++) + (++i);
10 11 12
10 + 12=22
k = (++i) + (++i);
11 11 12
11 + 12=23
