9. 숫자만 추출

import java.util.*;

class Main {
	public int solution(String str) {
		int answer = 0;
		char[] c = str.toCharArray();

		for (int i = 0; i < c.length; i++) {
			if (Character.isDigit(c[i])) {
				answer = answer * 10 + c[i] - 48;
			}
		}
		return answer;
	}

	public static void main(String[] args) {
		Main T = new Main();
		Scanner kb = new Scanner(System.in);
		System.out.println(T.solution(kb.next()));
	}
}

 

 

import java.util.*;

class Main {
	public int solution(String str) {
		String answer = "";
		char[] c = str.toCharArray();

		for (int i = 0; i < c.length; i++) {
			if (Character.isDigit(c[i]))
				answer += c[i];
		}
		return Integer.parseInt(answer);
	}

	public static void main(String[] args) {
		Main T = new Main();
		Scanner kb = new Scanner(System.in);
		System.out.println(T.solution(kb.next()));
	}
}

 

String += char