2021-05-07 자바페스티벌 끝(스마트인재개발원)

JavaFestival 알고리즘문제(배포).pptx

1.11MB

JavaFestival 알고리즘문제예시(1차배포).pptx

0.12MB

JavaFestival 알고리즘문제예시(2차배포) (1).pptx

0.69MB

JavaFestival 알고리즘문제예시(3차배포).pptx

0.12MB

package Chapter03;

import java.util.ArrayList;

public class ex_실습13반복문을_이용하여369 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		
		for(int i=0; i<100; i++) {
			System.out.print(i+" 박수 ");
			if(i%10 == 3 || i%10==6 || i%10 ==9) {
				System.out.print("짝");
			}
			
			if(i/10 == 3 || i/10==6 || i/10 ==9) {
				System.out.print("짝");
			}
			
			
			System.out.println();
		}

	}

}

package Chapter03;

import java.util.ArrayList;
import java.util.Scanner;

public class ex_실습08정수를몇개저장할지 {

	public static void main(String[] args) {
		ArrayList <Integer> random_array = new ArrayList <> ();  
		
		Scanner sc = new Scanner(System.in);
		System.out.print("정수 몇개?>");
		int get_num = sc.nextInt();
		for(int i = 0; i<get_num; i++) {
			int random_num = (int)(Math.random()*100+1);
			if(!random_array.contains(random_num)) {
				
				random_array.add(random_num);
				
			}else {
				get_num++;
			}
			
			
		}
		
		System.out.println(random_array);

	}

}
​

package Chapter03;

public class ex_실습094x42차원배열을만들고 {

	public static void main(String[] args) {
		
		int[][] array = new int[4][4];
		
		for(int a=0; a<10;) {
			
			int i = (int)(Math.random()*4);
			int j = (int)(Math.random()*4);
			
			int k = (int)(Math.random()*11
					);
			
			if(array[i][j] == 0) {
				array[i][j] = k;
				a++;
			}

			
		}
		
	
		for(int i = 0;  i<4; i++) {
			
			for(int j =0; j<4; j++  ) {
				
				System.out.print(array[i][j] + " ");
			}
			
			System.out.println();
		}
		
	}

}

package Chapter03;

import java.util.ArrayList;
import java.util.Scanner;

public class ex_실습05양의정수10개 {
	public static void main(String[] args) {
	
		Scanner sc = new Scanner(System.in);
		ArrayList <Integer> three_num = new ArrayList<>();
		ArrayList <Integer> real_three_num = new ArrayList<>();
	
		System.out.print("양의 정수 10개를 입력하시오>>");
		for(int i=0; i<10; i++) {
		three_num.add(sc.nextInt());
		}
		
		
		for(int j=0; j<10; j++) {
			if(three_num.get(j)%3 ==0) {
				real_three_num.add(three_num.get(j));
			}
			
		}
		
		System.out.print("3의 배수는");
		for(int k=0; k<real_three_num.size(); k++) {
			
			System.out.print(real_three_num.get(k)+" ");
			
		}
		
	}
}
​

package Chapter03;

import java.util.Scanner;

public class ex_실습06배열과반복문액수받아 {

	public static void main(String[] args) {
	
		Scanner sc = new Scanner(System.in);
		int [] unit = {50000,10000,1000,500,100,50,10,1};
		
		System.out.print("금액을 입력하시오>>");
		int input_num = sc.nextInt();
		
		for(int i=0; i<=unit.length-1; i++) {
			if(input_num/unit[i] !=0)
			{
				System.out.println(unit[i]+"원 짜리 : " + (input_num/unit[i]) + "개");
			}
			input_num = input_num%unit[i];
		}
		
	}

}

package Chapter03;

import java.util.Scanner;

public class ex_실습04_알파벳을입력 {

	public static void main(String[] args) {
		
		Scanner sc  = new Scanner(System.in);
		
		System.out.print("소문자 알파벳 하나를 입력하시오>>");
		String alp = sc.next();
		char alp_first = alp.charAt(0);
		int alp_num = (int)alp_first;
		int a_num = (int)'a';
		
	
		if(alp_num == a_num) {
			System.out.println((char)a_num);
		}else {
			for(int j = alp_num-a_num; j>-1; j--) {
				for(int i = a_num; i<=alp_num; i++) {
				
				System.out.print((char)i);
				
			}
			
			alp_num --;
			System.out.println();
			
			}
			
			
		}
			
		
		

	}

}

package Chapter03;

public class ex_실습02_2차원배열 {

	public static void main(String[] args) {
		int n [][] = {{1}, {1,2,3}, {1}, {1,2,3,4,}, {1,2}};
		
		for(int i = 0; i<n.length; i++) {
			for(int j = 0; j<n[i].length; j++ ) {
				
				System.out.print(n[i][j] + " ");
			}
			System.out.println();
		}

	}

}
​

package Chapter03;

import java.util.Scanner;

public class ex_실습03_실수입력받고별그리기 {
	public static void main(String[] args) {
		
	
	Scanner sc = new Scanner (System.in);
	System.out.print("정수를 입력하시오>>");
	int input_num = sc.nextInt();
	
	for(int i=0; i<input_num; i++) {
		for(int j=input_num-i; j>0; j--) {
			
			System.out.print("*");
			
		}
		
		System.out.println();
		
		}
	
	}
}

package Chapter03;

public class ex_041에서50합 {

	public static void main(String[] args) {
		int sum =0, i=1;
		while(true) {
			if(i>51) break;
			sum +=i;
			i++;
		}
		System.out.println(sum);
	}

}
​

package Chapter03;

public class ex_06실행오류 {

	public static void main(String[] args) {
	 int array[]= {1,2,3,4,5};
	 array[0] = -1;
	 int list[] = array;
	 System.out.println(list[0]);
	 array[1] =100;

	}

}

package Chapter03;

public class ex_011_100까지3의배수 {

	public static void main(String[] args) {
	
		int sum = 0, i =1;
		while(i<100) {
			if(i%3 !=0) {
				i++;
			}else sum+=i;
			i++;
			System.out.println(sum + " ");
		}
		
		System.out.println(sum);
	}

}