백준 10773 제로 (파이썬, 자바)

풀이 (파이썬)

import sys

N = int(sys.stdin.readline())

S = []

for _ in range(N):
    num = int(sys.stdin.readline())
    if num > 0:
        S.append(num)
    elif num == 0:
        S.pop()

print(sum(S))

 

풀이 (자바)

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;

public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader bf = new BufferedReader(new InputStreamReader(System.in));

        int K = Integer.parseInt(bf.readLine());

        List<Integer> nums = new ArrayList<>();

        for (int i = 0; i < K; i++) {
            int num = Integer.parseInt(bf.readLine());
            if (num != 0) {
                nums.add(num);
            } else {
                nums.remove(nums.size()-1);
            }
        }

        int rst = nums.stream().mapToInt(Integer::intValue).sum();
        System.out.println(rst);

    }
}