Question

我似乎无法解决这个问题，因为我很困。我不知道在if语句中该怎么做。任何帮助将不胜感激。

    Random coin1 = new Random();
    Random coin2 = new Random();
    Random coin3 = new Random();

    int count = 0;
    int heads = 0;

    System.out.println("Toss\tCoin1\tCoin2\tCoin3");

    while (heads < 3) {
        int c1 = coin1.nextInt(2);
        int c2 = coin2.nextInt(2);
        int c3 = coin3.nextInt(2);
        count++;
        if()

        System.out.println(count + "\t" +coin1 +"\t" + coin2 + "\t" +coin3);

Answer 1

您不需要if。您的随机值为0或1。假设值为1代表Head，则可以使用

heads = c1+c2+c3;

代替那个if。

Answer 2

如果假设扔了 heads ，nextInt()返回1，则将这些值的总和分配给heads。

heads = c1 + c2 + c3;

如果您使用if而不是nextBoolean()，则还有一个使用nextInt(2)的选项，如果扔了 heads ，它将返回true 。同样将变量修改为boolean而不是int，代码看起来像

while (heads < 3) {
     boolean c1 = coin1.nextBoolean();
     boolean c2 = coin2.nextBoolean();
     boolean c3 = coin3.nextBoolean();
     count++;
     heads = 0;
     heads += c1 ? 1 : 0; //incrementing heads if c1 is true
     heads += c2 ? 1 : 0;
     heads += c3 ? 1 : 0;
     if(c1 && c2 && c3){ }
     System.out.println(count + "\t" + c1 +"\t" + c2 + "\t" +c3);
}

在System.out.println(count + "\t" +coin1 +"\t" + coin2 + "\t" +coin3); coin1中也引用了Random对象，这意味着将打印出类似java.util.Random@74a14482的东西，而不是抛硬币的值。如果要打印0或1，则需要打印c1。（与2和3相同）

Answer 3

您可以使用Random的一个实例

    Random rnd = new Random();
    int count = 0,heads = 0;

    while (heads < 3) {
        int c1 = rnd.nextInt(2);
        int c2 = rnd.nextInt(2);
        int c3 = rnd.nextInt(2);
        count++;
        heads = c1+c2+c3;
        System.out.println(count + "\t" +c1 +"\t" + c2 + "\t" +c3);
    }

如果只想打印最终结果：

    Random rnd = new Random();
    int count = 0,heads = 0;
    int c1 = 0, c2 = 0, c3 = 0;

    while (heads < 3) {
        c1 = rnd.nextInt(2);
        c2 = rnd.nextInt(2);
        c3 = rnd.nextInt(2);
        count++;
        heads = c1+c2+c3;
    }
    System.out.println(count + "\t" +c1 +"\t" + c2 + "\t" +c3);

Answer 4

    //you can use only one rand obj to use Random()
    Random rand = new Random();

    //Initializing coins as 0
    //Values of coins will change once we get random 
    int coin1 = 0;
    int coin2 = 0;
    int coin3 = 0;

    //initializing heads and count as 0
    int heads = 0;
    int count = 0;

    while(heads < 3){
        //Assume '1' comes out for head and '0' for tail
         coin1 = rand.nextInt(2);
         coin2 = rand.nextInt(2);
         coin3 =  rand.nextInt(2);

         //if all three coins are '1' which is head; 
         //sum should be 1+1+1 = 3
         //while loop terminates because 3<3 is false
        heads = coin1+coin2+coin3;
        count++; //count = count +1;
    }
    //printing the value of count and coins
    System.out.println(count + "\t" +coin1 + "\t" + coin2 + "\t" +coin3);

正面或反面有3个硬币，直到所有3个硬币落在头上

4 个答案: