課題
12/05付試験のQ23〜Q38のついて考察せよ。
●コードと実行結果を示し、各問について考察すること。
実行結果public class Q23 { public static void main(String[] args) { int x,y; x = 100; x +=1; x--; y = 200 + x; System.out.println(y++); } }
300
実行結果public class Q24 { public static void main(String[] args) { int a=0, x=0; a=5; a +=3; x = ++a; System.out.println(x); } }
9
実行結果public class Q25 { public static void main(String[] args) { int a=9, b=3; a /= b; System.out.println(a %= b); } }
0
実行結果public class Q26 { public static void main(String[] args) { int i, j; for(i=0, j=0; i<3; i++) ++j; System.out.println(i * j); } }
9
実行結果public class Q27 { public static void main(String[] args) { int i=2; while(i-- > 0) System.out.print(i); } }
10
実行結果public class Q28 { public static void main(String[] args) { int num=10000; for(int i = 0; i < 4; i++) num >>= i; System.out.println(num); } }
156
実行結果public class Q29 { public static void main(String[] args) { int num =0; for(int i = 1; i <= 10; i++){ if(++num % i==0) num++; } System.out.println(++num); } }
12
実行結果public class Q30 { public static void main(String[] args) { int a = 9; if(a++ != 10 | a++ == 10) a++; System.out.println(a); } }
12
実行結果public class Q31 { public static void main(String[] args) { for( int i = 0; i< 5; i ++) System.out.println("i=="+ i ); System.out.println("Hello"); } }
i==0 i==1 i==2 i==3 i==4 Hello
実行結果public class Q32 { public static void main(String[] args) { int i; for( i= 0; i < 9; i +=3){} System.out.println(i); } }
9
実行結果public class Q33 { public static void main(String[] args) { for( int i = 0; i < 8; i ++){ System.out.println(i); i += 3; } } }
0 4
実行結果public class Q34 { public static void main(String[] args) { int i = 0; for( sayHello(); i <= 6; i += 3){ sayHello(); } } static void sayHello(){ System.out.println("Hello"); } }
Hello Hello Hello Hello
実行結果class Q35 { public static void main(String[] args) { Player p1 = new Player(); Player p2 = new Player(); p1.id = 1000; p2.id = 2000; p1.num += p1.id; p2.num += p2.id; System.out.println(Player.num); } } class Player{ int id = 0; static int num = 0; }
3000
実行結果public class Q36 { public static void main(String args[]) { Player p1 = new Player(); Player p2 = new Player(); p1.id = 1000; p2.id = 2000; Player.num += p1.id; Player.num += p2.id; System.out.println("p1.num == "+p1.num); System.out.println("p2.num == "+p2.num); } } class Player{ int id = 0; static int num = 0; }
p1.num == 3000 p2.num == 3000
実行結果public class Q37 { public static void main(String argv[]){ Card c1 = new Card(); Card c2 = new Card(); Card c3 = c1; c1.deposit = 1000; c2.deposit = 2000; c3.deposit = 3000; int sum = c1.deposit + c2.deposit + c3.deposit; System.out.println(sum); } } class Card{ int deposit; }
8000
実行結果public class Q38 { public static void main(String argv[]) { Card c1 = new Card(); Card c2 = c1; c1.deposit = 1000; c2.deposit = 2000; Bank.useCard(c1); Bank.useCard(c2); System.out.println(c1.deposit); System.out.println(c2.deposit); } } class Card{ int deposit; } class Bank{ public static void useCard(Card c){ c.deposit -= 500; } }
1000 1000