kh4일차
2022. 6. 23. 18:20ㆍ코딩/Java
public void exam4() {
Scanner sc = new Scanner(System.in);
System.out.println("============대/소문자 변환 프로그램============");
System.out.print("문자입력 : ");
char ch = sc.next().charAt(0);
System.out.println("====결과====");
if('a'<ch && ch<'z') {
System.out.println("소문자를 입력하였습니다");
int ch2=ch^32;
System.out.println("대문자로 변환 : "+(char)ch2);
}else if(65<ch && ch<90 ) {
System.out.println("대문자를 입력 하였습니다.");
int ch3=ch+32;
System.out.println("소문자로 변환 : "+(char)ch3);
}else {
System.out.println("잘못입력하셨습니다. 영문자를 입력해주세요");
}
}3일차 예시 다른풀이방법
스위치문
package kh.java.func;
import java.util.Scanner;
public class SwtichTest {
public void test1() {
Scanner sc = new Scanner(System.in);
System.out.print("1~3 사이의 정수를 입력하세요 : ");
int num = sc.nextInt();
switch (num) {
case 1:
System.out.println("1");
break;
case 2:
System.out.println("2");
break;
case 3:
System.out.println("3");
break;
default:
System.out.println("?");
break;
}
}
public void test2() {
Scanner sc = new Scanner(System.in);
System.out.println("문자열 입력 : ");
String str = sc.next();
switch (str) {
case "aa":
System.out.println("aaaaaa");
break;
case "bb":
System.out.println("bbbbbb");
break;
default:
break;
}
}
public void exam1() {
Scanner sc = new Scanner(System.in);
System.out.print("일수를 알고싶은 달을 입력하세요 : ");
int num = sc.nextInt();
switch (num) {
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:
System.out.println(num+"월달은 31일까지 있습니다.");
break;
case 2:
System.out.println("2월달은 28일까지 있습니다.");
break;
case 4:
case 6:
case 9:
case 11:
System.out.println(num+"월달은 30일까지 있습니다.");
break;
default:
System.out.println("잘못 입력하셨습니다.");
break;
}
}
public void exam2() {
Scanner sc = new Scanner(System.in);
System.out.println("장학금 지불 시스템 입니다.");
System.out.print("학점을 입력하세요(A,B,C,D,F)");
char ch = sc.next().charAt(0);
switch (ch) {
case 'A':
System.out.println("수고하셨습니다. 장학금을100% 드리겠습니다.");
break;
case 'B':
System.out.println("아쉽군요. 장학금을 50%지급해 드리겠습니다.");
break;
case 'C':
System.out.println("장학금을 바라시면 좀더 열심히 해주세요");
break;
case 'D':
System.out.println("크흠.....");
break;
case 'F':
System.out.println("학사경고입니다!!!.");
break;
default:
break;
}
}
public void exam3() {
Scanner sc = new Scanner(System.in);
System.out.println("=====계산기 프로그램=====");
System.out.print("연산자를 입력하세요 (+,-,*,/) : ");
char ch = sc.next().charAt(0);
System.out.print("첫번째 정수를 입력하세요 : ");
int num1 = sc.nextInt();
System.out.print("두번째 정수를 입력하세요 : ");
int num2 = sc.nextInt();
switch (ch) {
case '+':
System.out.println(num1 + "+" + num2 + "=" + (num1 + num2));
break;
case '-':
System.out.println(num1 + "-" + num2 + "=" + (num1 - num2));
break;
case '*':
System.out.println(num1 + "*" + num2 + "=" + num1 * num2);
break;
case '/':
System.out.println(num1 + "/" + num2 + "=" + (double) num1 / num2);
break;
default:
break;
}
}
}while문
package kh.java.func;
import java.util.Scanner;
public class WhileTest {
public void test1() {
// for(초기값;조건식;증감문)
// 초기값설정
int i = 0;
while (i < 5) {
System.out.println("안녕하세요");
i++;
}
}
public void ex1() {
Scanner sc = new Scanner(System.in);
System.out.print("몇변 출력하시겠습니까 : ");
int num1 = sc.nextInt();
int i = 0;
while (i < num1) {
System.out.println("안녕하세요");
i++;
}
}
public void ex2() {
Scanner sc = new Scanner(System.in);
System.out.println("2단입니다.");
int i = 0;
while (i < 9) {
i++;
System.out.printf("%d*%d=%d\n", 2, i, 2 * i);
}
}
public void ex3() {
Scanner sc = new Scanner(System.in);
System.out.print("몇단을 출력하시겠습니까? : ");
int dan = sc.nextInt();
int i = 0;
while (i < 9) {
i++;
System.out.printf("%d*%d=%d\n", dan, i, dan * i);
}
}
public void ex4() {
Scanner sc = new Scanner(System.in);
int i = 0;
int total = 0;
while (i < 5) {
i++;
System.out.print("정수 값을 입력하시오 : ");
int num1 = sc.nextInt();
total += num1;
}
System.out.println("입력한 5개의 정수의 합 : " + total);
}
public void ex5() {
Scanner sc = new Scanner(System.in);
System.out.print("첫번째 수 입력 : ");
int num1 = sc.nextInt();
System.out.print("두번째 수 입력 : ");
int num2 = sc.nextInt();
int total = 0;
if (num1 > num2) {
int i = num2;
while (i <= num1) {
total += i;
i++;
}
System.out.println(num2 + "~" + num1 + "의 정수의 합 : " + total);
} else if (num2 > num1) {
int i = num1;
while (i <= num2) {
total += i;
i++;
}
System.out.println(num1 + "~" + num2 + "의 정수의 합 : " + total);
}
}
public void ex5_1(){
Scanner sc = new Scanner(System.in);
System.out.print("첫번째 수 입력 : ");
int num1 = sc.nextInt();
System.out.print("두번째 수 입력 : ");
int num2 = sc.nextInt();
int total = 0;
int result1 = num1<num2?num1:num2;
int result2 = num1<num2?num2:num1;
int i = result1;
while(i <= result2) {
total += i;
i++;
}
System.out.println(result1 + "~" + result2 + "의 정수의 합 : " + total);
}
public void ex6() {
Scanner sc = new Scanner(System.in);
System.out.print("숫자 입력 : ");
int num1 = sc.nextInt();
int i = 0;
int sum = 0;
while(i<num1+1) {
sum += i;
i+=2;
}
System.out.println("짝수들의 합은 : "+sum);
}
}for문
package kh.java.func;
import java.util.Scanner;
public class ForTest {
public void test1() {
for (int i = 0; i < 5; i++) {
System.out.println("안녕하세요");
}
}
public void ex1() {
Scanner sc = new Scanner(System.in);
System.out.print("몇번 출력하시겠습니까?");
int num1 = sc.nextInt();
for (int i = 0; i < num1; i++) {
System.out.println("안녕하세요");
}
}
public void ex2() {
Scanner sc = new Scanner(System.in);
System.out.println("구구단 2단 출력하기");
for (int i = 0; i < 9; i++) {
int num = 2;
System.out.println(num + "*" + (i + 1) + "=" + num * (i + 1));
}
}
public void ex3() {
Scanner sc = new Scanner(System.in);
System.out.print("몇단을 출력하시겠습니까?");
int num1 = sc.nextInt();
System.out.println(num1 + "단 입니다.");
for (int i = 0; i < 9; i++) {
System.out.println(num1 + "*" + (i + 1) + "=" + num1 * (i + 1));
}
}
public void ex4() {
Scanner sc = new Scanner(System.in);
int total = 0;
for (int i = 0; i < 5; i++) {
System.out.print("정수값을 입력하시오 : ");
int num1 = sc.nextInt();
total += num1;
// sum += sc.nextInt();
}
System.out.println("입력한 5개의 정수의 합 : " + total);
}
public void ex5() {
Scanner sc = new Scanner(System.in);
System.out.print("첫번째 수 입력 : ");
int num1 = sc.nextInt();
System.out.print("두번째 수 입력 : ");
int num2 = sc.nextInt();
int total = 0;
if (num1 > num2) {
for (int i = num2; i <= num1; i++) {
total += i;
}
System.out.println(num2 + "~" + num1 + "의 정수의 합 : " + total);
} else if (num2 > num1) {
for (int i = num1; i <= num2; i++) {
total += i;
}
System.out.println(num1 + "~" + num2 + "의 정수의 합 : " + total);
}
}
public void ex6() {
Scanner sc = new Scanner(System.in);
System.out.print("숫자 입력 : ");
int num1 = sc.nextInt();
int total = 0;
for (int i = 0; i <= num1; i += 2) {
total += i;
}
System.out.println("짝수들의 합은 : " + total);
}
public void ex7() {
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++) {
System.out.println("i : " + i + " / j :" + j);
}
}
}
public void ex8() {
for (int i = 2; i <= 9; i++) {
for (int j = 1; j <= 9; j++) {
System.out.printf("%d*%d=%d\t", i, j, i * j);
}
System.out.println();
}
// for (int j = 1; j <= 9; j++) {
// System.out.printf("%d*%d=%d\t", 2, j, 2 * j);
// }
// System.out.println();
// for (int j = 1; j <= 9; j++) {
// System.out.printf("%d*%d=%d\t", 3, j, 3 * j);
// }
// System.out.println();
// for (int j = 1; j <= 9; j++) {
// System.out.printf("%d*%d=%d\t", 4, j, 4 * j);
// }
}
public void ex9() {
for (int i = 1; i <= 9; i++) {
for (int j = 2; j <= 9; j++) {
System.out.printf("%d*%d=%d\t", j, i, j * i);
}
System.out.println();
}
}
}이중for문으로 별찍기
package kh.java.func;
import java.util.Scanner;
public class ForExam {
public void ex1() {
for (int i = 0; i < 5; i++) {
System.out.print("*");
}
}
public void ex2() {
for (int i = 0; i < 5; i++) {
System.out.println("*");
}
}
public void ex3() {
for (int i = 0; i < 5; i++) {
for (int j = 0; j < 5; j++) {
System.out.print("*");
}
System.out.println();
}
}
public void ex4() {
for (int i = 0; i < 5; i++) {
for (int j = 1; j < 6; j++) {
System.out.print((i + 1));
}
System.out.println();
}
}
public void ex5() {
for (int i = 0; i < 5; i++) {
for (int j = 1; j < 6; j++) {
System.out.print(j);
}
System.out.println();
}
}
public void ex6() {
int k = 0;
for (int i = 0; i < 5; i++) {
for (int j = 1; j < 6; j++) {
System.out.print(j + k);
}
k++;
System.out.println();
}
}
public void ex7() {
int k = 4;
for (int i = 0; i < 5; i++) {
for (int j = 1; j < 6; j++) {
System.out.print(j + k);
}
k--;
System.out.println();
}
}
public void ex8() {
for (int i = 1; i < 6; i++) {
for (int j = 0; j < i; j++) {
System.out.print("*");
}
System.out.println();
}
}
public void ex9() {
for (int i = 0; i < 6; i++) {
for (int j = 0; j < 5 - i; j++) {
System.out.print("*");
}
System.out.println("");
}
}
public void ex10() {
for (int i = 0; i < 6; i++) {
for (int j = 0; j < i; j++) {
System.out.print(" ");
}
for (int j = 0; j < 5 - i; j++) {
System.out.print("*");
}
System.out.println("");
}
}
public void ex11() {
for (int i = 1; i < 6; i++) {
for (int j = 0; j < 5 - i; j++) {
System.out.print(" ");
}
for (int j = 0; j < i; j++) {
System.out.print("*");
}
System.out.println("");
}
}
public void ex12() {
for (int i = 0; i < 6; i++) {
for (int j = 0; j < i; j++) {
System.out.print("*");
}
System.out.println("");
}
for (int i = 0; i < 6; i++) {
for (int j = 0; j < 4 - i; j++) {
System.out.print("*");
}
System.out.println("");
}
}
public void ex13() {
for (int i = 0; i < 4; i++) {
for (int j = 0; j < 5 - i; j++) {
System.out.print("*");
}
System.out.println("");
}
for (int i = 1; i < 6; i++) {
for (int j = 0; j < i; j++) {
System.out.print("*");
}
System.out.println("");
}
}
public void ex16() {
for (int i = 0; i < 5; i++) {
for (int j = 0; j < 4 - i; j++) {
System.out.print(" ");
}
for (int j = 0; j < (2 * i) + 1; j++) {
System.out.print("*");
}
System.out.println("");
}
}
public void ex17() {
for (int i = 0; i < 5; i++) {
for (int j = 0; j < i; j++) {
System.out.print(" ");
}
for (int j = 0; j < 9 - 2 * i; j++) {
System.out.print("*");
}
System.out.println("");
}
}
public void ex18() {
for (int i = 0; i < 5; i++) {
for (int j = 0; j < 4 - i; j++) {
System.out.print(" ");
}
for (int j = 0; j < (2 * i) + 1; j++) {
System.out.print("*");
}
System.out.println("");
}
for (int i = 0; i < 5; i++) {
for (int j = 0; j < i + 1; j++) {
System.out.print(" ");
}
for (int j = 0; j < 7 - 2 * i; j++) {
System.out.print("*");
}
System.out.println("");
}
}
public void ex19() {
for (int i = 0; i < 5; i++) {
for (int j = 0; j < 5 - i; j++) {
System.out.print("*");
}
for (int j = 0; j < (2 * i) + 1; j++) {
System.out.print(" ");
}
for (int j = 0; j < 5 - i; j++) {
System.out.print("*");
}
System.out.println("");
}
for (int i = 1; i < 5; i++) {
for (int j = 0; j < i + 1; j++) {
System.out.print("*");
}
for (int j = 0; j < 9 - 2 * i; j++) {
System.out.print(" ");
}
for (int j = 0; j < i + 1; j++) {
System.out.print("*");
}
System.out.println("");
}
}
public void ex20() {
for (int i = 0; i < 5; i++) {
for (int j = 0; j < i + 1; j++) {
System.out.print("*");
}
for (int j = 0; j < 9 - 2 * i; j++) {
System.out.print(" ");
}
for (int j = 0; j < i + 1; j++) {
System.out.print("*");
}
System.out.println("");
}
for (int i = 1; i < 5; i++) {
for (int j = 0; j < 5 - i; j++) {
System.out.print("*");
}
for (int j = 0; j < 2 * i + 1; j++) {
System.out.print(" ");
}
for (int j = 0; j < 5 - i; j++) {
System.out.print("*");
}
System.out.println("");
}
}
public void ex21() {
for (int i = 0; i < 5; i++) {
for (int j = 0; j < i; j++) {
System.out.print(" ");
}
for (int j = 0; j < 9 - 2 * i; j++) {
System.out.print("*");
}
System.out.println("");
}
for (int i = 1; i < 5; i++) {
for (int j = 0; j < 4 - i; j++) {
System.out.print(" ");
}
for (int j = 0; j < (2 * i) + 1; j++) {
System.out.print("*");
}
System.out.println("");
}
}
}