2022年02月09日 22:35

고태욱

edited: 2022年02月09日 22:36

자바로 풀어봤습니다.

import java.util.Scanner;
public class test {
 // x 계수 찾기
 public static Integer findCoeffx(String equation) {
 if(equation.split("x|X")[0].equals("")) {
 return 1;
 }else if(equation.split("x|X")[0].equals("-")){
 return -1;
 }else if((equation.contains("x")|equation.contains("X"))==false){
 return 0;
 }else {
 return Integer.parseInt(equation.split("x|X")[0]);
 }
 }
 // y 계수 찾기
 public static Integer findCoeffy(String equation) {
 if(equation.split("x|X|y|Y")[1].equals("+")) {
 return 1;
 }else if(equation.split("x|X|y|Y")[1].equals("-")){
 return -1;
 }else if(equation.split("y|Y")[0].equals("")|equation.split("y|Y")[0].equals("-")) {
 return 0;
 }else if((equation.contains("y")|equation.contains("Y"))==false) {
 return 0;
 }else {
 return Integer.parseInt(equation.split("x|X|y|Y")[1]);
 }
 }
 // 상수 찾기
 public static Integer findConstant(String equation) {
 if(equation.contains("=")==false) {
 return 0;
 }else {
 return Integer.parseInt(equation.split("=")[1]);
 }
 }
 public static void main(String[] args) {
 Scanner scan = new Scanner(System.in);
 String[] equations = new String[2];
 int[] coeffx = new int[2];
 int[] coeffy = new int[2];
 int[] constant = new int[2];
 // 일차방정식 입력 받기
 int count = 0; 
 float answery, answerx;
 String inputX, inputY; 
 while(true) {
 System.out.printf("%d번째 일차방정식(ax+by=c):", count+1);
 equations[count] = scan.next();
 // 일차방정식의 계수 뽑아서 배열에 저장
 coeffx[count] = findCoeffx(equations[count]);
 coeffy[count] = findCoeffy(equations[count]);
 constant[count] = findConstant(equations[count]);
 // 만약 계수가 0이면 다시 입력
 if(coeffx[count]==0|coeffy[count]==0|constant[count]==0) {
 System.out.println("잘못 입력하셨습니다. 다시 입력하시오.");
 }else {
 count++;
 }
 // 방정식을 2개 입력했는지 
 if(count==2) {
 break;
 }
 }
 // y 값 구하기
 int diffy = coeffy[0]*coeffx[1] - coeffy[1]*coeffx[0];
 int diffConstant = constant[0]*coeffx[1] - constant[1]*coeffx[0]; 
 answery = (float)diffConstant/diffy;
 // x 값 구하기
 answerx = (constant[0]-coeffy[0]*answery)/coeffx[0];
 // 결과 출력
 System.out.printf("x : %f\n", answerx);
 System.out.printf("y : %f", answery);
 }
}