не вижу ошибки
package com.javarush.task.task05.task0532;
/*
Задача по алгоритмам
*/
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class Solution {
public static void main(String[] args) throws Exception {
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
int n = Integer.parseInt(reader.readLine());
int max = 0;
if (n > 0) {
for (int i = 0; i < n ; i++) {
int number = Integer.parseInt(reader.readLine());
if (max < number ) max = number;
}
System.out.println(max);
}
}
}