4 и 5 пункты.
package com.javarush.task.task05.task0529;
import java.io.BufferedReader;
import java.io.InputStreamReader;
/*
Консоль-копилка
*/
public class Solution {
public static void main(String[] args) throws Exception {
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
int sum = 0;
while (true){
String s = reader.readLine();
if (s.equals("сумма"))break;
else {
int b = Integer.parseInt(s);
sum+=b;
System.out.println(sum);
}
}
}
}