23 lines
790 B
C++
23 lines
790 B
C++
#include <vector>
|
|
#include <algorithm>
|
|
|
|
/**
|
|
* 74. Search a 2D Matrix
|
|
* Write an efficient algorithm that searches for a value target in an m x n integer matrix matrix. This matrix has the following properties:
|
|
* - Integers in each row are sorted from left to right.
|
|
* - The first integer of each row is greater than the last integer of the previous row.
|
|
*/
|
|
|
|
class Solution {
|
|
public:
|
|
static bool searchMatrix(const std::vector<std::vector<int>>& matrix, int target) {
|
|
auto it = std::upper_bound(matrix.begin(), matrix.end(), std::vector<int>{target}, [](const std::vector<int>& x, const std::vector<int>& y) {
|
|
return x.front() < y.front();
|
|
});
|
|
if (it == matrix.begin())
|
|
return false;
|
|
it = std::prev(it);
|
|
return std::binary_search(it->begin(), it->end(), target);
|
|
}
|
|
};
|