私の課題では、試行の入力を使用して、ソーダのキャップを開けて勝ったかどうかを調べて、賞を獲得した人の平均を決定するファイルを作成する必要があります。彼らが勝つチャンスは 5 分の 1 です。個別の試行の平均を取得したら、試行を読み戻して平均を計算します。ファイルから double を読み取ろうとすると問題が発生します。これはこれまでの私のコードです。
import java.util.Scanner;
import java.io.File;
import java.io.PrintWriter;
import java.io.IOException;
public class BottleCapPrize
{
public static void main(String[] args) throws IOException
{
double averageBottles = 0.0;
double randNum = 0.0;
int bottleSum = 0;
int numBottles = 1;
int bottle = 0;
int maxRange = 6;
int minRange = 1;
int oneTrial = 0;
int winPrize = 1;
double token = 0;
int totalSumCaps = 0;
Scanner in = new Scanner(System.in);
//Generates bottle number for first test
randNum = Math.random();
bottle = ((int)((randNum) * (maxRange - minRange)) + minRange);
//construct an object called outFile to allow access to output methods of the PrintWriter class
PrintWriter outFile = new PrintWriter(new File("trials.txt"));
//Gets users input for how many trials
System.out.print("Enter the amount of trials: ");
int trials = in.nextInt();
System.out.println();
//Check averages for entered trials
for (int loop = 1; loop <= trials; loop++)
{
//Clears out the loops variables each time through
if(loop != 0)
{
averageBottles = 0;
bottleSum = 0;
oneTrial = 0;
numBottles = 0;
}
for(int x = 1; x <= 20; x++)
{
if(x == 20) //One trial is completed
{
averageBottles = bottleSum / x;
//Replaces the old bottle number for a new bottle
randNum = Math.random();
bottle = ((int)((randNum) * (maxRange - minRange)) + minRange);
}
else if(bottle == winPrize)
{
oneTrial = numBottles;
if(oneTrial == 0)
{
oneTrial = 1;
}
//Replaces the old bottle number for a new bottle
randNum = Math.random();
bottle = ((int)((randNum) * (maxRange - minRange)) + minRange);
}
else if(bottle != winPrize) //not a winner, gets new bottle and increments the number of bottles tested
{
//Replaces the old bottle number for a new bottle
randNum = Math.random();
bottle = ((int)((randNum) * (maxRange - minRange)) + minRange);
oneTrial = numBottles;
numBottles ++;
}
bottleSum += oneTrial; //Adds the sum from each trial
}
outFile.println("Trial " + loop + "." + " " + averageBottles); //Prints the averages to the file
System.out.println("Trial " + loop + "." + " " + averageBottles);
//outFile.println("Trial " + "=" + " " + averageBottles); //Prints the averages to the file
//System.out.println("Trial "+ "=" + " " + " " + averageBottles);
}//end of for loop
outFile.close ( );//close the file when finished
//Read the trial data back in and calculate the average
File fileName = new File("trials.txt");
Scanner inFile = new Scanner(fileName);
//read file and get data
while(inFile.hasNext())
{
token = inFile.nextDouble();
totalSumCaps += token;
}
inFile.close();
double totalAverageCaps = totalSumCaps / trials;
//Print results
System.out.println();
System.out.println("The average number of caps opened in order to win a prize is: " + totalAverageCaps);
}
}