sclass LCSortedPairIndex {
  long[] pairs;
  int[] index;
  
  *(long[] *pairs) {
    index = lc_sortedPairIndex(pairs);
  }
  
  int get(long pair) {
    int i = intArrayBinarySearchWithComparator(index, (a, b) -> cmp(pairs[a], pairs[b]), pair);
  }
}