メモ（Java 道場I）

ミスったところ１（引数の指定が抜けている）

import java.util.Scanner;

class Main {
  public static void main(String[] args) {
    Scanner scanner = new Scanner(System.in);
    
    System.out.print("名前：");
    String firstName=scanner.next();
    
    System.out.print("名字：");
    String lastName=scanner.next();
    
    System.out.print("年齢：");
    int age=scanner.nextInt();
    
    System.out.print("身長(m)：");
    double height=scanner.nextDouble();
    
    System.out.print("体重(kg)：");
    double weight=scanner.nextDouble();
    
    printData();
    //正：printData(firstName,lastName,age,height,weight);
    
  }
  
  public static void printData() {
    //正：public static void printData(String firstName,String lastName,int age,double height,double weight) {
    System.out.println("名前は"+fullName+"です");
    //正：System.out.println("名前は"+fullName(firstName,lastName)+"です");
    System.out.println("年齢は"+age+"歳です");
    
    if(age>=20){
      System.out.println("成年者です");
    }else{
      System.out.println("未成年者です");
    }
    
    System.out.println("身長は"+height+"mです");
    System.out.println("体重は"+weight+"kgです");
    
  }
  
  
  public static String fullName(firstName,lastName) {
    //正：public static String fullName(String firstName,String lastName) {
    return firstName+lastName;
    
  }
  
  
}

ミスった２（変数bmiの定義し忘れと、Math.roundの場所がだめ）

class Person {
  
  public static void printData(String firstName,String lastName,int age,double height,double weight) {
    System.out.println("名前は"+Person.fullName(firstName,lastName)+"です");
    System.out.println("年齢は"+age+"歳です");
    
    if(age>=20){
      System.out.println("成年者です");
    }else{
      System.out.println("未成年者です");
    }
    
    System.out.println("身長は"+height+"mです");
    System.out.println("体重は"+weight+"kgです");
    
    
    //正：double bmi=bmi(height,weight);　※誤：記載なし
    System.out.println("BMIは"+bmi+"です");
    //正：System.out.println("BMIは"+Math.round(bmi)+"です");
  }
  
  public static double bmi(double height,double weight) {
    return Math.round(weight/height/height);
    //正：return weight/height/height;
    
  }
  
  public static String fullName(String firstName,String lastName) {
    return firstName+" "+lastName;
    
  }
  
  
}