Medium
Minimum K to Reduce Array Within Limit — C++
Full explanation · Time O(nlogn + nlogr) · Space O(1)
// Time: O(nlogr + nlogn)
// Space: O(1)
// binary search
class Solution {
public:
int minimumK(vector<int>& nums) {
const auto& binary_search = [](auto left, auto right, const auto& check) {
while (left <= right) {
const auto& mid = left + (right - left) / 2;
if (check(mid)) {
right = mid - 1;
} else {
left = mid + 1;
}
}
return left;
};
const auto& ceil_divide = [](int a, int b) {
return (a + b - 1) / b;
};
const auto& check = [&](int k) {
int64_t result = 0;
for (const auto& x : nums) {
result += ceil_divide(x, k);
if (result > static_cast<int64_t>(k) * k) {
return false;
}
}
return true;
};
const auto& right = max(ranges::max(nums), static_cast<int>(ceil(sqrt(size(nums)))));
return binary_search(1, right, check);
}
};