public class LastNDigits {
/**
Extracts the last N digits from a given number.
The approach:
- To get the last N digits, compute: number % (10^N)
- This avoids string manipulation and is efficient.
Parameters:
number : the original integer
digits : how many digits to extract from the end
Returns:
The last N digits as an integer.
*/
public static int getLastNDigits(int number, int digits) {
// Compute 10^digits using Math.pow (returns double)
// Cast to int because modulo requires integer operands
int divisor = (int) Math.pow(10, digits);
// Modulo gives the remainder, which is exactly the last N digits
return number % divisor;
}
public static void main(String[] args) {
// Example values
int number = 987654321;
int digits = 4;
// Extract the last N digits
int result = getLastNDigits(number, digits);
// Display the result
System.out.println("Original number: " + number);
System.out.println("Digits requested: " + digits);
System.out.println("Last " + digits + " digits: " + result);
}
}
/*
run:
Original number: 987654321
Digits requested: 4
Last 4 digits: 4321
*/
