839. Time Complexity: Grid DP Table

function countPaths(rows, cols) {
  const dp = Array.from({ length: rows }, () => Array(cols).fill(1))

  for (let r = 1; r < rows; r++) {
    for (let c = 1; c < cols; c++) {
      dp[r][c] = dp[r - 1][c] + dp[r][c - 1]
    }
  }

  return dp[rows - 1][cols - 1]
}