class Solution {
    public int maxRemovals(String source, String pattern, int[] targetIndices) {
        HashSet<Integer> set = new HashSet<>();
        for(int x: targetIndices){
            set.add(x + 1);
        }
        int n = source.length(), m = pattern.length();
        int[][] f = new int[n + 1][m + 1];
        for(int i = 0; i <= n; i ++ ){
            Arrays.fill(f[i], Integer.MIN_VALUE);
        }

        f[0][0] = 0;
        for(int i = 1; i <= n; i ++ ){
            for(int j = 0; j <= m; j ++ ){
                f[i][j] = f[i - 1][j] + (set.contains(i) ? 1 : 0);
                if(j > 0 && source.charAt(i - 1) == pattern.charAt(j - 1)){
                    f[i][j] = Math.max(f[i][j], f[i - 1][j - 1]);
                }
            }
        }

        return f[n][m];
    }
}