Question

我想打印出Math.random（）少于0.5的次数以及有多少次数大于0.5。所以我使用int sum变量并每次增加它，如代码所示：

package shapes;

public class Main {


public static void main(String[] args) {

    for (int i=1; i<6; i++){
    int sum1=0;
    if(Math.random()<0.5){
         System.out.println("head");
         System.out.println(Math.random());
         sum1++;
         System.out.println("sum of head"+sum1);

     }else {
         int sum2=0;
         System.out.println("tail");
         System.out.println(Math.random());
         sum2++;
         System.out.println("sum of tail"+sum2);
        }
    }

    }

            }

我的输出是：

tail
0.2420579681161944
sum of tail1
head
0.712979930711983
sum of head1
tail
0.28072067461911476
sum of tail1
head
0.5897197845744805
sum of head1
head
0.6735600614954825
sum of head1

我希望输出如下：

tail
0.2420579681161944
head
0.712979930711983
tail
0.28072067461911476
head
0.5897197845744805
head
0.6735600614954825
sum of head 3 
sum of tail 2

我实际上试图将sum1 ++和sum2 ++放在不同的地方，但没有奏效。感谢

Answer 1

每次在for循环中将sum重置为0。将你的sums变量声明移出循环。

int sum1=0;
int sum2=0; 
for (int i=1; i<6; i++){
double val = Math.random();    
if(val<0.5){
     sum1++;
 }else {
     sum2++;
    }
     System.out.println("sum of head "+sum1);
     System.out.println("sum of tail "+sum2);    
 }

Answer 2

做：

public static void main(String[] args) throws IOException
    {
         int sum1=0,sum2=0;
         for (int i=1; i<6; i++){

                if(Math.random()<0.5){
                     System.out.println("head");
                     System.out.println(Math.random());
                     sum1++;
                }else { // end of if
                     System.out.println("tail");
                     System.out.println(Math.random());
                     sum2++;

                }// end of else
         }// end of for
         System.out.println("sum of head "+sum1);
         System.out.println("sum of tail "+sum2);

      }// end of main

如何修复运行次数的输出

2 个答案: