Display the sorted output of a merge of any number of

static void merge(int[][]a){
        int[]index=new int[a.length];
        int total=0;
        for(int i=0;i

pop one element from every sorted array and put into a heap, pop 1 from heap and display, pop another element from the sorted array that min element came from to heap, repeat until all arrays are empty and heap is empty

public Integer[] mergeSort(ArrayList input, int start, int end) {
  if(start == end) {
     return input.get(end);
  }
  if(start == end-1) {
     return merge(input.get(start), input.get(end));
  }
  Integer[] first = mergeSort(input, start, (start + end)/2);
  Integer[] second = mergeSort(input, (start + end)/2 + 1, end);
  return merge(first, second);
}
// merge(first, second) - is regular merging of two arrays

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