Evaluate the given expression when the value of a=2 and b=3

b*=a++ - ++b + ++a;
System.out.println("a= "+a); 
System.out.println("b= "+b);

A store has purchased some cola cans of various brands. It purchased 50 cans @ ₹15 per can, 30 cans @ ₹20 per can and 40 cans @ ₹21 per can. Write a Java program to compute how much amount did the store pay.