#include <iostream>
#include <vector>
#include <algorithm>
class Set {
private:
std::vector<int64_t> vec;
Set MergeSet(Set const second, Set const first) {
Set tmp;
tmp.vec.insert(tmp.vec.end(), second.vec.begin(), second.vec.end());
tmp.vec.insert(tmp.vec.end(), first.vec.begin(), first.vec.end());
return tmp;
}
int64_t BinSearchPosition(std::vector<int64_t> v,
int64_t digit, int64_t left,
int64_t right
) {
int64_t mid = (left + right) / 2;
int64_t Digit_mid = v[mid];
if (digit == Digit_mid) {
return -1;
}
if (left + 1 == right)
return mid ? mid + 1 : 0;
if (digit > Digit_mid) {
return BinSearchPosition(v, digit, mid, right);
} else {
return BinSearchPosition(v, digit, left, mid);
}
}
int64_t BinSearch_Remove(std::vector<int64_t> v,
int64_t digit,
int64_t left,
int64_t right) {
int64_t mid = (left + right) / 2;
int64_t Digit_mid = v[mid];
if (digit == Digit_mid)
return mid;
if (left + 1 == right) {
return -1;
}
if (digit > Digit_mid) {
return BinSearch_Remove(v, digit, mid, right);
} else {
return BinSearch_Remove(v, digit, left, mid);
}
}