/**
 * ?????§?????????
 * FX????????§????????°?????????????????¨????????????????????¨??§????????????????????????????????¨?????§????????????????????°????????????100???????????? 1000???????????????????????????????????? 1?????? 108???????????£??????????£??????¨???(108??? ?????? 100???) ???? 1000?????? == 8000??????????????????????????¨?????§????????????
 * <p>
 * ???????????¨?????????????????????t?????????????????? Rt(t=0,1,2,,,n???1)?????\?????¨??????????????????????????§??????????????? Rj???Ri (?????????,j>i??¨??????) ????????§???????±??????????????????????
 * <p>
 * ??\???
 * ?????????????????´??°n?????????????????????????¶????n????????´??° Rt(t=0,1,2,,,n???1) ?????????????????????????????????
 * <p>
 * ??????
 * ?????§??????????????????????????????????????????
 * <p>
 * ??¶?´?
 * 2???n???200,000
 * 1???Rt???10e9
 */

import java.util.*;

public class Main {
	public static void main(String[] args) {
		Scanner stdIn = new Scanner(System.in);

		int t = stdIn.nextInt();
		int[] profitT = new int[t];

		for (int i = 0; i < t; i++) {
			profitT[i] = stdIn.nextInt();
		}

		int maxProfit = profitT[1] - profitT[0];

		int min = profitT[0];
		for (int i = 1; i < t; i++) {
			if (maxProfit < profitT[i] - min) {
				maxProfit = profitT[i] - min;
			}
			if (min > profitT[i]) {
				min = profitT[i];
			}
		}
		System.out.println(maxProfit);
	}
}
/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