UVA_10074_Take the Land

#include<iostream>      
#include<sstream>      
#include<string>      
#include<vector>      
#include<list>      
#include<set>      
#include<map>      
#include<stack>      
#include<queue>      
#include<algorithm>      
#include<cmath>      
#pragma warning(disable:4996)      
using std::cin;
using std::cout;
using std::endl;
using std::stringstream;
using std::string;
using std::vector;
using std::list;
using std::pair;
using std::set;
using std::multiset;
using std::map;
using std::multimap;
using std::stack;
using std::queue;
int process_row(const vector<vector<bool>>&matrix,const int &n,const int &m)
{
	int area = 0;
	for (int i = 0; i < n; i++)//      
	{
		for (int j = i; j < n; j++)//      
		{
			vector<pair<bool, int>>dp(m);
			for (int row = i; row <= j; row++)
			{
				for (int column = 0; column < m; column++)
				{
					if (matrix[row][column])
					{
						dp[column].first = true;
					}
				}
			}
			int maximum = 0;
			if (!dp[0].first)
			{
				dp[0].second++;
				maximum = 1;
			}
			for (int k = 1; k < m; k++)
			{
				if (!dp[k].first)
				{
					if (dp[k - 1].first)
					{
						dp[k].second++;
					}
					if (!dp[k - 1].first)
					{
						dp[k].second = dp[k - 1].second + 1;
						maximum = std::max(maximum, dp[k].second);
					}
				}
			}
			area = std::max(area, maximum*(j - i + 1));
		}
	}
	return area;
}
int process_column(const vector<vector<bool>>&matrix, const int &n, const int &m)
{
	int area = 0;
	for (int i = 0; i < n; i++)//      
	{
		for (int j = i; j < n; j++)//      
		{
			vector<pair<bool, int>>dp(m);
			for (int column = i; column <= j; column++)
			{
				for (int row = 0; row < m; row++)
				{
					if (matrix[row][column])
					{
						dp[row].first = true;
					}
				}
			}
			int maximum = 0;
			if (!dp[0].first)
			{
				dp[0].second++;
				maximum = 1;
			}
			for (int k = 1; k < m; k++)
			{
				if (!dp[k].first)
				{
					if (dp[k - 1].first)
					{
						dp[k].second++;
					}
					if (!dp[k - 1].first)
					{
						dp[k].second = dp[k - 1].second + 1;
					}
					maximum = std::max(maximum, dp[k].second);
				}
			}
			area = std::max(area, maximum*(j - i + 1));
		}
	}
	return area;
}
int main()
{
	//freopen("input.txt", "r", stdin);
	//freopen("output.txt", "w", stdout);
	int n,m; 
	while (cin>>n>>m&&n&&m)
	{
		vector<vector<bool>>matrix(n, (vector<bool>)m);
		for (int i = 0; i < n; i++)
		{
			for (int j = 0; j < m; j++)
			{
				short isTree; cin >> isTree;
				if (isTree)
				{
					matrix[i][j]=true;
				}
			}
		}
		int area = 0;
		area = std::max(area, process_row(matrix, n, m));
		area = std::max(area, process_column(matrix, m, n));
		cout << area << endl;
	}
	return 0;
}