class Main
{
	public static void main( String[] args )
	{
		java.util.Scanner sc = new java.util.Scanner( System.in );
		int n = sc.nextInt();
		int max = -1000000000, min = sc.nextInt();
		int in;
		for( int ct = 1 ; ct < n ; ct++ ){
			in = sc.nextInt();
			if( in-min > max )max = in-min;
			if( in < min )min = in;
		}
		System.out.printf( "%d\n" , max );
	}
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz