Java loop and increment problem

Question

Can any one tell me what is the problem in my program?

String a[],b[];
int c[] = new int[b.length];

for (int j = 0; j < a.length; j++) {
    for (int k = 0; k < b.length; k++) {
        if (b[k].equals(a[j])) {
            c[k]++;
        } else {
            c[k] = 0;
        }
    }
}

I have thousands of words stored in a HashMap. Now I want to check in every file that how many time one word occurred from allWords.

Can you point out mistake in my program or give me your idea that how I can do it?

Answer 1

You could count words while reading your files and store on a Map already.. Assuming last word on file is "-1" and there's only one word in a line, even if the word is "happy birthday", I'd do something like this:

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Scanner;

public class StackOverflow {

@SuppressWarnings("unchecked")
public static void main(String[] args) {
    Scanner scanner = new Scanner(System.in);
    Map<String, Integer> countedWords = new HashMap<String, Integer>();
    int numberOfWords = 0;
    String word = "";
    while (true) {
        word = scanner.nextLine();
        if (word.equalsIgnoreCase("-1")) {
            break;
        }
        if (countedWords.containsKey(word)) {
            numberOfWords = countedWords.get(word);
            countedWords.put(word, ++numberOfWords);
        } else {
            countedWords.put(word, 1);
        }
    }
    Iterator it = countedWords.entrySet().iterator();
    while (it.hasNext()) {
        Map.Entry pairs = (Map.Entry)it.next();
        System.out.println(pairs.getKey() + " = " + pairs.getValue());
    }
}
}

Answer 2

I think this line is resetting your counters unnecessarily:

newData[j] = 0;

Try removing it:

for (int j = 0; j < oneFileWords.length; j++) {
    for (int k = 0; k < allWords.length; k++) {
        if (allWords[k].equals(oneFileWords[j])) {
            newData[j]++;
        }
    }
}

If you want to keep a separate count for each word in each file then you will need to use two dimensional array.

int newData[][] = new int[oneFileWords.length][allWords.length];

You can then access it using newData[j][k].