私はプログラミングが初めてで、単純なじゃんけんゲームを作成しようとしています。基本的に、while ループを使用して、ユーザーに再生 (または続行) するかどうかを尋ねます。彼らがそれを望まなくなったら、プログラムは総ゲーム数、勝利数、敗北数、勝率を出力しなければなりません。プログラム全体が動作するようになりましたが、勝率が 0.0% ではない場合でも常に 0.0% と表示されます。ゼロ除算エラーを回避するために、すでに if ステートメントを使用しました。実行時エラーもコンパイラ エラーも発生していないので、何かが足りないか、見つけられない論理エラーがあります。これからもスキャナーを使い続けたいと思います。
import java.util.Scanner;
public class RockPaperScissors {
/*
* Program allows user to play Rock, Paper and Scissors as many times as desired by entering Y until they enter N.
* Program will print amount of games played, amount lost, amount won and percentage won.
* User must enter "Y", "N", "Rock", "Paper" or "Scissors" with correct capitalization and spelling.
*/
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
int playerWins = 0;
int compWins = 0;
int gamesPlayed = 0;
while (true) {
System.out.println("Do you want to play Rock Paper Scissors (Y/N): ");
String play = input.nextLine();
// user terminates game and program prints number of wins, losses and percentage of wins.
if (play.equals("N")) {
System.out.println("You played a total of " + gamesPlayed + " matches against the computer");
System.out.println("The computer won " + compWins + " matches");
System.out.println("You won " + playerWins + " matches");
// 0% wins when no games are played.
if (gamesPlayed == 0) {
System.out.println("You won 0% of the time!");
break;
} else if (gamesPlayed > 0) {
double totalWins = (int)(playerWins / gamesPlayed) * 100;
System.out.println("You won " + totalWins + "% of the time!");
break;
}
} else if ((!play.equals("N")) && (!play.equals("Y"))) {
System.out.println("Invalid entry");
} else {
System.out.println("Welcome to Rock, Paper and Scissors!");
System.out.print("Select \"Paper\", \"Rock\" or \"Scissors\": ");
String decision = input.nextLine();
System.out.println("Your selection: " + decision);
// random number generator producing integer values between 1 to 3 for computer's choices.
// 1 is for Rock, 2 is for Paper and 3 is for Scissors.
int num = (int)(Math.random() * (3-0) + 1);
switch (num) {
// Computer picks Rock
case 1:
if (decision.equals("Rock")) {
System.out.println("Tie, you and the computer selected rock");
gamesPlayed++;
} else if (decision.equals("Paper")) {
System.out.println("You win, paper beats rock!");
gamesPlayed++;
playerWins++;
} else if (decision.equals("Scissors")) {
System.out.println("Computer wins, rock beats scissors!");
gamesPlayed++;
compWins++;
} else {
System.out.println(decision + " is not a valid input");
}
break;
case 2:
// computer picks Paper
if (decision.equals("Rock")) {
System.out.println("Computer wins, rock beats paper!");
gamesPlayed++;
compWins++;
} else if (decision.equals("Paper")) {
System.out.println("Tie, you and the computer selected paper");
gamesPlayed++;
} else if (decision.equals("Scissors")) {
System.out.println("You win, scissors beats paper");
gamesPlayed++;
playerWins++;
} else {
System.out.println(decision + " is not a valid input");
}
break;
case 3:
// computer picks Scissors
if (decision.equals("Rock")) {
System.out.println("You win, rock beats scissors");
gamesPlayed++;
playerWins++;
} else if (decision.equals("Paper")) {
System.out.println("Computer wins, scissors beats paper");
gamesPlayed++;
compWins++;
} else if (decision.equals("Scissors")) {
System.out.println("Tie, you and the computer selected scissors");
gamesPlayed++;
} else {
System.out.println(decision + " is not a valid input");
}
break;
}
}
}
}
}