Problem8.java

/**
 * Created by Jackson on 4/30/16.
 */
public class Problem8{
    public static void main(String[] args){
        String numbers = "73167176531330624919225119674426574742355349194934" +
        "96983520312774506326239578318016984801869478851843" +
        "85861560789112949495459501737958331952853208805511" +
        "12540698747158523863050715693290963295227443043557" +
        "66896648950445244523161731856403098711121722383113" +
        "62229893423380308135336276614282806444486645238749" +
        "30358907296290491560440772390713810515859307960866" +
        "70172427121883998797908792274921901699720888093776" +
        "65727333001053367881220235421809751254540594752243" +
        "52584907711670556013604839586446706324415722155397" +
        "53697817977846174064955149290862569321978468622482" +
        "83972241375657056057490261407972968652414535100474" +
        "82166370484403199890008895243450658541227588666881" +
        "16427171479924442928230863465674813919123162824586" +
        "17866458359124566529476545682848912883142607690042" +
        "24219022671055626321111109370544217506941658960408" +
        "07198403850962455444362981230987879927244284909188" +
        "84580156166097919133875499200524063689912560717606" +
        "05886116467109405077541002256983155200055935729725" +
        "71636269561882670428252483600823257530420752963450";

        long largestProduct = 0;
        long currentProduct = 0;
        long temp;
        for(int i=14;i<numbers.length();i++){
            if((i + 12) > numbers.length() - 1) break;
            currentProduct = getProduct(i, numbers);
            if(largestProduct < currentProduct){
                temp = largestProduct;
                largestProduct = currentProduct;
                currentProduct = temp;
            }
        }
        System.out.println("The largest product of 13 number in a row is " + largestProduct);
    }
    public static long getProduct(int index, String numbers){
        long product = 1;
        for(int i=index;i<=index+12;i++){
            product *= Integer.parseInt(Character.toString(numbers.charAt(i)));
        }
        return product;
    }
}