homework question

[warped basalt]

We don't code for people. Show us what you tried and try to tell us what confuses you with the problem

Small tip, break the problem is smaller problems. Then solve them one by one

Ex. The first small problem you have to solve is getting the user's input, then define a function that takes an integer as parameter and return another integer...

[frosty iron]

;compile java

public class Main {
public static final int sumOfEven(final int n)
throws RuntimeException
{
   if (n < 0) throw new RuntimeException("Not a valid entry");
   int sum = 0;
   for(int i = 0; i <= n; ++i)
   {
      if ((i % 2) == 0) sum += i;
   }
   return sum;
}

public static void main(String args[])
throws RuntimeException
{
   int sum = 0;
/*
   final String input = "4";
   final int n = Integer.parseInt(input);
   sum = sumOfEven(n);
   System.out.println(sum);
*/

   sum = sumOfEven(10);
   System.out.println(sum);

   sum = sumOfEven(101);
   System.out.println(sum);
   sum = sumOfEven(2);
   System.out.println(sum);
   sum = sumOfEven(1);
   System.out.println(sum);
   sum = sumOfEven(-1);
   System.out.println(sum);
}

}

[wicked heart]

Program Output

30
2550
2
0

Compiler Output

Exception in thread "main" java.lang.RuntimeException: Not a valid entry
at Main.sumOfEven(example.java:5)
at Main.main(example.java:34)

fd26#6261 | 140ms | java | jdk 18.0.0 | godbolt.org

[frosty iron]

in C++ use cout / cin

[blazing mountain]

https://onlinegdb.com/G3Mo5Jt9m

[frosty iron]

wait that's a different question 😄