# The for-loop The product of numbers from a to b

I need to write a program that prints the product of all integer numbers from a to b (a < b).

Include a and exclude b from the product.

Sample Input 1:

1 2

Sample Output 1:

1

2

Here is my code:

```import java.util.Scanner;
class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
long a = scanner.nextLong();
long b = scanner.nextLong();
long multiply = 0;

for(long i = a; i<b; i++){
multiply = i * (i+1);
}
System.out.println(multiply);
}
}
```

What I’m doing wrong? Please a hint 🙂

UPDATE:

It didn’t help either.

Test input:

1 2

Correct output:

1

0

```import java.util.Scanner;
class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
long a = scanner.nextLong();
long b = scanner.nextLong();
long multiply = 0;
for(long i = a+1; i<b; i++){
multiply = i * (i+1);
if(multiply==2){
--multiply;
}

}
System.out.println(multiply);
}
}
```

You should start with `multiply = 1` and then keep multiplying it with the next integers.

```import java.util.Scanner;

public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
long a = scanner.nextLong();
long b = scanner.nextLong();
long multiply = 1;

for (long i = a; i < b; i++) {
multiply *= i;
}
System.out.println(multiply);
}
}
```

A sample run:

```1 2
1
```

Another sample run:

```2 5
24
```
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