//股票问题，数组中存放每天股票价格，求获得最大利润 #include <iostream> #include <vector> using namespace std;

int main()
{
        vector<int> vVec;
	int len = 0, temp = 0;
	while(cin>>temp) vVec.push_back(temp);
	len = vVec.size();
	if(len <= 1)  return 0;
	int min = vVec[0], max = 0;
	for (int i = 1; i < len; ++i)
	{
		if(vVec[i] < min)  
		{
			min = vVec[i];
			continue;
		}
		if(max < vVec[i] - min) max = vVec[i] - min;
	}
	cout<< max;
	return 0;
}