leetcode-daily/cpp/2305/LC230513CN.cpp

25 lines
650 B
C++

#include <algorithm>
#include <vector>
#include <unordered_set>
/**
* 2441. Largest Positive Integer That Exists With Its Negative
*
* Given an integer array nums that does not contain any zeros, find the largest positive integer k such that -k also exists in the array.
* Return the positive integer k. If there is no such integer, return -1.
*/
class LC230513 {
public:
static int findMaxK(const std::vector<int>&) noexcept;
};
int LC230513::findMaxK(const std::vector<int>& n) noexcept {
std::unordered_set<int> s(n.begin(), n.end());
int ret = -1;
for (int i: s)
if (s.count(-i))
ret = std::max(ret, std::abs(i));
return ret;
}