solution.js

/**
 * @param {number[][]} matrix
 * @return {number[]}
 */
var luckyNumbers = function (matrix) {
    const M = matrix.length;
    const N = matrix[0].length;
    const isRowMin = new Array(M);
    const isColumnMax = new Array(M);
    for (let i = 0; i < M; i++) {
        isRowMin[i] = new Array(N).fill(false);
        isColumnMax[i] = new Array(N).fill(false);
        const rowMin = Math.min(...matrix[i]);
        for (let j = 0; j < N; j++) {
            if (matrix[i][j] === rowMin) {
                isRowMin[i][j] = true;
            }
        }
    }
    for (let j = 0; j < N; j++) {
        let columnMax = 0;
        for (let i = 0; i < M; i++) {
            columnMax = Math.max(columnMax, matrix[i][j]);
        }
        for (let i = 0; i < M; i++) {
            if (matrix[i][j] === columnMax) {
                isColumnMax[i][j] = true;
            }
        }
    }
    const result = [];
    for (let i = 0; i < M; i++) {
        for (let j = 0; j < N; j++) {
            if (isRowMin[i][j] && isColumnMax[i][j]) {
                result.push(matrix[i][j]);
            }
        }
    }

    return result;
};