[백준] 10828 스택 - C++, Java

https://www.acmicpc.net/problem/10828

 

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문제 풀이

 

C++

#include<stdio.h>
#include<string.h>
int stack[100001];
int main()
{
    int n, i, key = -1;
    char input[6];
    scanf("%d", &n);

    for(i = 0; i < n; i++) {
        scanf("%s", input);
        if(strcmp(input, "push") == 0) {
            scanf("%d", &stack[++key]);
        }
        else if(strcmp(input, "pop") == 0) {
            if(key == -1) printf("-1\n");
            else printf("%d\n", stack[key--]);
        }
        else if(strcmp(input, "size") == 0) {
            printf("%d\n", key+1);
        }
        else if(strcmp(input, "empty") == 0) {
            if(key == -1) printf("1\n");
            else printf("0\n");
        }
        else if(strcmp(input, "top") == 0) {
            if(key == -1) printf("-1\n");
            else printf("%d\n", stack[key]);
        }
    }

    return 0;
}

 

자바

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.StringTokenizer;

public class Main {

	public static void main(String[] args) throws IOException{
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int n = Integer.parseInt(br.readLine());
		int[] arr = new int[n];
		int size = 0;
		
		for (int i = 0; i < n; i++) {
			StringTokenizer st = new StringTokenizer(br.readLine(), " ");
			
			switch (st.nextToken()) {
			case "push":
				arr[size] = Integer.parseInt(st.nextToken());
				size++;
				break;
				
			case "pop":
				if (size == 0) {
					System.out.println(-1);
				}
				else {
					System.out.println(arr[size - 1]);
					size--;
				}
				break;
			
			case "size":
				System.out.println(size);
				break;
				
			case "empty":
				if (size == 0) {
					System.out.println(1);
				}
				else {
					System.out.println(0);
				}
				break;
				
			case "top":
				if (size == 0) {
					System.out.println(-1);
				}
				else {
					System.out.println(arr[size - 1]);
				}
				break;

			default:
				break;
			}
		}

	}

}

 

예전에 자바로 풀어둔 게 있길래 정리 겸 같이 업로드..