Iterate through each digit in a number

Question

I am trying to create a program that will tell if a number given to it is a \"Happy Number\" or not. Finding a happy number requires each digit in the number to be squared,

Answer 1

This code returns the first number (after 1) that fits your description.

public static void main(String[] args) {
    int i=2;
    // starting the search at 2, since 1 is also a happy number
    while(true) {
        int sum=0;
        for(char ch:(i+"").toCharArray()) { // casting to string and looping through the characters.
            int j=Character.getNumericValue(ch);
            // getting the numeric value of the current char.
            sum+=Math.pow(j, j);
            // adding the current digit raised to the power of itself to the sum.
        }
        if(sum==i) {
            // if the sum is equal to the initial number
            // we have found a number that fits and exit.
            System.out.println("found: "+i);
            break;
        }
        // otherwise we keep on searching
        i++;
    }
}