c나 c++은 포인터나 참조를 쓸수 있으나 java에서는 주소를 쓸수 없음으로
함수 단위에서 공유할 것이라면 기본자료형을 쓰는 것이아니라 구조체로 묶어서 공유해야 한다.
이렇게 두개의 값을 공유하기위해
Exam[] exams = new Exam[3];
int current=0;
ExamsList새로운 클래스를 생성한다.
public class Examlist {
Exam[] exams;
int current=0;
}
다시 프로그램으로 돌아와서
public static void main(String[] args) {
Examlist list = new Examlist(); // Examlist 을 참조 하기위해 list 변수를 선언
list.exams= new Exam[3];
list.current=0;
.
.
case 1: case 1:
inputlist(exams,current); -> inputlist(list);
private static void inputlist(Exam[] exams, int current) -> private static void inputlist(Examlist list)
exams[current]=exam; -> list.exams[list.current]=exam;
current++ list.current++;
public class ListProgram {
public static void main(String[] args) {
Examlist list = new Examlist();
list.exams= new Exam[3];
list.current=0;
boolean Keeploop =true;
int menu;
while(Keeploop) {
menu= selectmenu();
switch (menu) {
case 1:
inputlist(list);
break;
case 2:
printlist(list);
break;
case 3:
System.out.println("시스템을 종료합니다");
Keeploop=false;
break;
default:
}
}
}
private static int selectmenu() {
Scanner sc = new Scanner(System.in);
System.out.println("1.성적입력");
System.out.println("2.성적출력");
System.out.println("3.종료");
int menu =sc.nextInt();
return menu;
}
private static void inputlist(Examlist list) {
Scanner sc = new Scanner(System.in);
int current = list.current;
int kor;
int math;
int eng;
do {
System.out.printf("%d번쨰국어성적을 입력하세요",current+1);
kor =sc.nextInt();
if(kor<0||kor>100)
System.out.println("입력범위를 확인하세요");
} while (kor<0||kor>100);
do {
System.out.printf("%d번쨰수학성적을 입력하세요",current+1);
math =sc.nextInt();
if(math<0||math>100)
System.out.println("입력범위를 확인하세요");
} while (math<0||math>100);
do {
System.out.printf("%d번쨰영어성적을 입력하세요",current+1);
eng =sc.nextInt();
if(eng<0||eng>100)
System.out.println("입력범위를 확인하세요");
} while (eng<0||eng>100);
Exam exam = new Exam();
exam.kor=kor;
exam.math=math;
exam.eng=eng;
Exam[] exams = list.exams;
int size = list.current;
if(exams.length ==size) {
// 크기가 5개 더 큰 새로운 배열생성
Exam[] temp = new Exam[size+5];
for(int i=0; i<size; i++)
temp[i]= exams[i];
list.exams=temp;
}
list.exams[list.current]=exam;
list.current++;
}
private static void printlist(Examlist list) {
int total;
float avg;
int size =list.current;
Exam[] exams=list.exams;
for(int i=0; i<size; i++) {
Exam exam = exams[i];
int kor= exam.kor;
int eng= exam.eng;
int math= exam.math;
total= kor+eng+math;
avg=total/3.0f;
System.out.printf("%d번째 성적입니다\n",i+1);
System.out.printf("국어성적:%d\n",kor);
System.out.printf("수학성적:%d\n",math);
System.out.printf("영어성적:%d\n",eng);
System.out.printf("총점:%d\n",total);
System.out.printf("평균:%6.2f\n",avg);
}
}
}