萌新20分，大佬帮忙看一哈

import java.util.Arrays;
import java.util.Scanner;

public class P1005 {
	public static int n,m;
	public static int[][] arr;
	public static boolean[][] f;
	
	//返回列
	public static int fun(int i) {
		int min = 0;
		int l=0,r=m-1;
		while (true) {
			if (f[i][l]==false && f[i][r]==false) {
				break;
			}
			if (f[i][l]==true) {
				l++;
			}
			if (f[i][r]==true) {
				r--;
			}
		}
		return arr[i][l]<arr[i][r]?l:r;
	}
	
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		n = scan.nextInt();
		m = scan.nextInt();
		long sum = 0;
		arr = new int[n][m];
		f = new boolean[n][m];
		for (int i=0;i<n;i++) {
			for (int j=0;j<m;j++) {
				arr[i][j] = scan.nextInt();
			}
		}
		for (int j=1;j<=m;j++) {		//取的次数
			for (int i=0;i<n;i++) {		//第i行
				int k = fun(i);
				f[i][k] = true;
				sum += (long)arr[i][k]*(long)((int)Math.pow(2, j));
			}
		}
		System.out.println(sum);
	}
}