LeetCode/cpp/kth-smallest-element-in-a-sorted-matrix.cpp
Matej Focko 2351dfd0ee
chore: unwrap one layer
Signed-off-by: Matej Focko <mfocko@redhat.com>
2023-12-12 14:36:00 +01:00

52 lines
954 B
C++

#include <algorithm>
#include <cassert>
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
int kthSmallest(vector<vector<int>>& matrix, int k)
{
int low = matrix.front().front();
int high = matrix.back().back();
while (low < high) {
int mid = low + (high - low) / 2;
int rank = 0;
for (const auto& row : matrix) {
rank += upper_bound(row.begin(), row.end(), mid) - row.begin();
}
if (rank < k) {
low = mid + 1;
} else {
high = mid;
}
}
return low;
}
};
int main()
{
Solution s;
vector<vector<int>> m;
int k;
m = {
{ 1, 5, 9 },
{ 10, 11, 13 },
{ 12, 13, 15 }
};
k = 8;
assert(s.kthSmallest(m, k) == 13);
m = { { -5 } };
k = 1;
assert(s.kthSmallest(m, k) == -5);
}