Question

i am having a problem with multipling a simple int value (1) with the values from a char-array:

public void doStuff(String values)
{
    char[] numbers = values.toCharArray();
    int result = 1;

    for (int i = 0; i < numbers.length; i++)
    {
        System.out.println(numbers[i] + " " + result);
        result *= numbers[i];
    }

    // more stuff here
}

in my case the input string-parameter is “73167”. in the line “result *= numbers[i]” result should be 7 after the first iteration, but debug info in eclipse says that result = 55.
any hints??

Answer 1

Your problem is that "73167" isn’t a number. It’s a string made of the characters "7", "3", "1", "6", "7". char in Java are Unicode code points, and '7' is 55 in ASCII/UTF-8. You want to do

result *= Character.getNumericValue(numbers[i]);

Doc for: Character.getNumericValue(char)