The JCF Stack class is used to instantiate a stack:
Stack< Integer > intStack = new Stack< Integer >() ;
The statements
Int k = 77;
IntStack.push(k*k) ;
Use the primitive type int instead of the wrapper type Integer.These statements

Question

Quizplus · Accepted Answer

The statements will compile and execute correctly because Java performs autoboxing, which automatically converts int to Integer, when necessary. Therefore, k*k will be converted to a Integer object and pushed onto the stack without any issues.

The JCF Stack Class Is Used to Instantiate a Stack