Computer Science 210

Data Structures

Fall 2019, Siena College

Sum1ToNBetter BlueJ Project

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Sum1ToNBetter Source Code

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/** * Example Sum1ToN - a method that returns the sum of the integer * values from 1 to a given number -- now using a more efficient * formula for the computation * * @author Jim Teresco, The College of Saint Rose, CSC 202, Fall 2012 * @version Fall 2019 */ public class Sum1ToNBetter { /** compute and return the sum of the numbers from 1 to a given limit @param limit the limit to which numbers are added @return the sum of the numbers from 1 to limit */ public static int sumNumbersTo(int limit) { // we just compute this using our mathematical formula return limit * (limit+1) / 2; } /** test the sumNumbersTo method. @param args not used */ public static void main(String[] args) { // for this example, we will just print out a few of these sums int firstSum = sumNumbersTo(10); System.out.println("The sum of the numbers 1-10 is " + firstSum); int secondSum = sumNumbersTo(82); System.out.println("The sum of the numbers 1-82 is " + secondSum); int thirdSum = sumNumbersTo(96352); System.out.println("The sum of the numbers 1-96352 is " + thirdSum); // or we can use this within a loop for (int number = 1; number <= 9; number++) { // and we can use the value as part of a printout or any other expression // if we do not want or need to save it in a variable System.out.println("The sum of the numbers 1-" + number + " is " + sumNumbersTo(number)); } } }