# LeetCode 1380. Lucky Numbers in a Matrix

https://leetcode.com/problems/lucky-numbers-in-a-matrix/description/

## 題目大意

找出同時是所屬 row 中最小亦是 column 中最大的該幸運數字

## 思考

對每個 row 都找出最小，然後檢查它是不是 column 中的最大就好

class Solution
{
public:
    vector<int> luckyNumbers(vector<vector<int>> &matrix)
    {
        for (const auto &row : matrix)
        {
            auto min = min_element(row.begin(), row.end());
            if (*min == maxInCol(matrix, distance(row.begin(), min)))
                return {*min};
        }

        return {};
    }

private:
    int maxInCol(vector<vector<int>> &matrix, int j)
    {
        int ans = 0;
        const int n = matrix.size();
        for (int i = 0; i < n; ++i)
        {
            ans = max(ans, matrix[i][j]);
        }

        return ans;
    }
};