class Solution {
    public String smallestStringWithSwaps(String s, List<List<Integer>> pairs) {
        char[] ca = s.toCharArray();

        List<Integer>[] adj = new List[ca.length];
        for (int i = 0; i < ca.length; i++) adj[i] = new ArrayList<>();

        for (List<Integer> pair: pairs) {
            adj[pair.get(0)].add(pair.get(1));
            adj[pair.get(1)].add(pair.get(0));
        }

        int allFreq[][] = new int[ca.length][];

        for (int i = 0; i < ca.length; i++) {
            if (adj[i].isEmpty()) continue;

            if (allFreq[i] == null) collect(i, ca, adj, allFreq, new int[26]);

            System.out.println(ca[i] + " " + Arrays.toString(allFreq[i]));

            for (int j = 0; j <26; j++)
                if (allFreq[i][j] > 0) {
                    ca[i] = (char)('a' + j);
                    allFreq[i][j]--;
                }
        }

        return new String(ca);
    }

    private void collect(int pos, char[] ca, List<Integer>[] adj, int[][] allFreq, int[] freq) {
        if (allFreq[pos] != null) return;
        allFreq[pos] = freq;

        freq[ca[pos]-'a']++;
        for (int next: adj[pos]) collect(next, ca, adj, allFreq, freq);
    }
}