void huffman_codes(Huff_pair* polje, int size){
    Node minHeap[size];
    for (int i = 0; i < size; ++i){
      minHeap[i].data.push_back(polje[i].symbol);
      minHeap[i].val = polje[i].prob;
      minHeap[i].size = 1;
    }

    for (int i=size; i>1; i--){
        sort(minHeap, i);
        for (int j = 0; j < (unsigned int) minHeap[i-2].size; j++){
          codewords[minHeap[i-2].data[j]] = "1" + codewords[minHeap[i-2].data[j]];
        }
        for (int j = 0; j < (unsigned int) minHeap[i-1].size; j++){
          codewords[minHeap[i-1].data[j]] = "0" + codewords[minHeap[i-1].data[j]];
        }
        minHeap[i-2].data.insert(minHeap[i-2].data.end(), minHeap[i-1].data.begin(), minHeap[i-1].data.end());
        minHeap[i-2].val += minHeap[i-1].val;
        minHeap[i-2].size += minHeap[i-1].size;
    }
}