CodeForces 375 B. Maximum Submatrix 2 - c++编程基础

写法似乎太暴力了。。。

B. Maximum Submatrix 2 time limit per test 2 seconds memory limit per test 512 megabytes input standard input output standard output

You are given a matrix consisting of digits zero and one, its size is n × m. You are allowed to rearrange its rows. What is the maximum area of the submatrix that only consists of ones and can be obtained in the given problem by the described operations

Let's assume that the rows of matrix a are numbered from 1 to n from top to bottom and the columns are numbered from 1 to m from left to right. A matrix cell on the intersection of the i-th row and the j-th column can be represented as (i, j). Formally, a submatrix of matrix ais a group of four integers d, u, l, r (1 ≤ d ≤ u ≤ n; 1 ≤ l ≤ r ≤ m). We will assume that the submatrix contains cells (i, j) (d ≤ i ≤ u; l ≤ j ≤ r). The area of the submatrix is the number of cells it contains.

Input

The first line contains two integers n and m (1 ≤ n, m ≤ 5000). Next n lines contain m characters each ― matrix a. Matrix a only contains characters: "0" and "1". Note that the elements of the matrix follow without any spaces in the lines.

Output

Print a single integer ― the area of the maximum obtained submatrix. If we cannot obtain a matrix of numbers one, print 0.

Sample test(s) input

1 1
1

output

input

2 2
10
11

output

input

output

#include 
  
   
#include 
   
     #include 
    
      #include 
     
       using namespace std; char map[5500][5500]; int h[5500][5500],n,m,ans=0; bool cmp(int a,int b) { return a>b; } int main() { scanf("%d%d",&n,&m); for(int i=0;i