[코딩연습] 메소드 생성 연습 2

 

풀이

import java.util.Scanner;

public class Quiz01 {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
        
		System.out.print("수를 입력하세요 : ");
		int number = scan.nextInt();
		
		System.out.println(sum(number));
        
		scan.close();
    }
    
    public static int sum(int a) {
		int sum = 0;
		for (int i = 0; i < a; i++) {
			sum += i;
			if (sum > 100) {
				break;
			}
		}
		return sum;
	}
}

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풀이

import java.util.Scanner;

public class Quiz01 {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
        
		System.out.print("5개의 수를 입력하세요 : ");
		int num1 = scan.nextInt();
		int num2 = scan.nextInt();
		int num3 = scan.nextInt();
		int num4 = scan.nextInt();
		int num5 = scan.nextInt();
		
		min(num1, num2, num3, num4, num5);
        
		scan.close();
    }
    
   public static void printMin(int num1,int num2,int num3,int num4,int num5) {
		//System.out.println("최소값은 " + Math.min(num1, Math.min(num2, Math.min(num3, Math.min(num4, num5)))));
		
        
        int min = num1;
		if (min > num2) {
			min = num2;
		}
		if (min > num3) {
			min = num3;
		}
		if (min > num4) {
			min = num4;
		}
		if (min > num5) {
			min = num5;
		}
		System.out.println("최소값은 " + min);
    }
    
}

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중요한문제! 면접문제로 자주 나온다고 한다.

 

풀이

import java.util.Scanner;

public class Quiz01 {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
        
        System.out.print("수를 입력하세요 : ");
		int number = scan.nextInt();
		
		System.out.println(prime(number));
		
		
		scan.close();
        
    }
    
    public static boolean prime(int a) {
		for (int i = 2; i <= Math.sqrt(a); i ++) { // 루트를 씌운다
			if (a % i == 0) {
				return false;
			}
		}
		return true;
}