Chapter 2 Exercise 11, Introduction to Java Programming, Tenth Edition Y. Daniel LiangY.

(Population projection) Rewrite Programming Exercise 1.11 to prompt the user to enter the number of years and displays the population after the number of years. Use the hint in Programming Exercise 1.11 for this program. The population should be cast into an integer.

import java.util.Scanner;
 
public class ProgrammingEx2_11 {
 
 public static void main(String[] args) {
  long newPop = 0, current = 312032486;
  int time;
  int birth, death, immigrant;
 
  Scanner input = new Scanner(System.in);
 
  System.out.print("Enter the number of years:");
  int v = input.nextInt();
 
  for (int i = 1; i <= v; i++) {
   // Convert time to second
   time = i * 365 * 24 * 60 * 60;
   // Calculating population increase/decrease in each case
   birth = time / 7;
   death = time / 13;
   immigrant = time / 45;
   // calculate new population
   newPop = current + birth - death + immigrant;
 
  }
 
  System.out.println("The population in " + v + "years is " + newPop);
 }
 
}