Sentinel:A sentinel is a special value used in programming to mark the end of data input, allowing programs to know when to stop processing.
Flag:In programming, a flag is a boolean variable that acts as an indicator or signal for certain conditions. It helps control the flow of execution within loops or conditional statements.
Loop Control Variable: A loop control variable is typically an integer variable that keeps track of the current iteration count in a loop. It helps control how many times the loop will execute based on certain conditions.