public class Apriori{
    public static void main (String args[]){
        System.out.println ("Implementing Apriori Algorithm");
        String trans[] = {"MONKEY", "DONKEY", "MAKE", "MUCKY", "COKIE"};
        String items[] = new String [11];
        int freq [] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} ;
        int k = 0;
        for (int p = 0; p <trans.length; p++) {
            String word = trans[p];
            for (int i = 0; i <word.length(); i++) {
                String temp = String.valueOf(word.charAt(i));
                boolean flag = true;
                int j = 0;
                while ( j < k && flag)  {
                    if (temp.equals(items[j])){
                        freq[j]++;
                        flag = false;
                    }
                    else{
                        j++;
                    }
                }
                if (flag) {
                    items[k] = temp;
                    freq[k]++;
                    k++;
                }
            }
        }
        System.out.println ("Step 1 : Counting Transaction For Each Item:");
        System.out.println();
        System.out.println ("Item" + "\t\t" + "Number of Transactions");
        for (int i = 0; i < freq.length; i++) {
            System.out.println (items[i] + "\t\t" + freq[i]);
        }
        System.out.println();
        for (int i = 0; i < freq.length; i++){
            if (freq[i] < 3) {
                freq[i] = 0;
                items[i] = "";
            }
        }
        System.out.println();
        System.out.println ("Step 2 : Discrading Items with less than 3 Transactions :");
        System.out.println();
        System.out.println ("Item" + "\t\t" + "Number of Transactions");
        for (int i = 0; i < freq.length; i++) {
            if (!items[i].equals("") && freq[i] != 0){
                System.out.println (items[i] + "\t\t" + freq[i]);
            }
        }
        int max = -10;
        String maxVal1 = "";
        for (int i = 0; i < freq.length; i ++) {
            if (freq[i] > max){
                max = freq[i];
                maxVal1 = items[i];
            }
        }
        max = -10;
        String maxVal2 = "";
        for (int i = 0; i < freq.length; i ++) {
            if (!items[i].equals(maxVal1) && freq[i] > max){

                max = freq[i];
                maxVal2 = items[i];
            }
        }
        System.out.println();
        System.out.println ("Step 3:");
        System.out.println ("The top two items that are the most transacted are  " + maxVal1 + "  and   " + maxVal2);
        System.out.println();
        max = -10;
        String contendors [] = new String [10];
        k = 0;
        System.out.println ("Step 4:");
        System.out.println ("The contendors for the third item that is transacted most with " +  maxVal1 + " and " + maxVal2 + " are:");
        for (int i = 0; i <freq.length; i++){
            if ( !items[i].equals ("") && !items[i].equals(maxVal1) &&!items[i].equals(maxVal2)){
                contendors[k] = items[i];
                System.out.println (contendors[k]);
                k++;
            }
        }
        System.out.println();
        max = -10;
        String maxVal3 = "";
        for (int i = 0; i <k; i++){
            String temp = contendors[i];
            int sumCount = 0;
            for (int j = 0; j < trans.length; j++) {
                String temp1 = trans[j];
                int count = 0, count1 = 0, count2 = 0;
                for (int t = 0; t < temp1.length(); t++){
                    if (String.valueOf(temp1.charAt(t)).equals (maxVal1)){
                        count1++;
                    }
                    else if (String.valueOf(temp1.charAt(t)).equals (maxVal2)){
                        count2++;
                    }
                    else if (String.valueOf(temp1.charAt(t)).equals (temp)){
                        count++;
                    }
                }
                if (count != 0 && count1 != 0 &&  count2 !=0 ){
                    sumCount++;
                }
            }
            System.out.println (temp + " appears with " + maxVal1 + " and " + maxVal2 + " " + sumCount + " times ");
            if (sumCount > max){
                max = sumCount;
                maxVal3 = temp;
            }
        }
        System.out.println();
        System.out.println ("The set of three items that appear the most together are " +  maxVal1 + maxVal2 + maxVal3) ;
        System.out.println();
    }
}