java系统。出来println不是打印输出

Question

下面是我查找偶数斐波那契数并添加它们的代码：

 package a;
 import java.util.*;

public class A {

 //this about finding Even Fibonacci numbers and adding them to sum.

public static void main(String[] args) {
    Scanner in = new Scanner(System.in);
    int t = in.nextInt();
    int[] n = new int[t];
    int[] nn = new int[t];
    int i,j,sum;
    for(int a0 = 0; a0 < t; a0++){
        n[a0] = in.nextInt();            
    }
    nn[0]=1;
    for(i = 0 ; i<t;i++){
        sum = 0;
        for(j= 1;j<n[i];j++){                
            nn[j] = j+nn[j-1];
            if(nn[j]%2==0)
                {
                sum += nn[j];
                }
            }            
        System.out.println(sum); //this is not printing the output
    }
}
}

样本输入

二, 10 一百

样本输出

十, 44

问题是这行System.out.println(sum);没有打印任何内容

有什么想法吗

Answer 1

在您的代码中

for(int a0 = 0; a0 < t; a0++){
    n[a0] = in.nextInt();            
}

问题是程序正在等待您输入t个整数。我不知道你想要什么值，但是把它改成这样

for(int a0 = 0; a0 < t; a0++){
    n[a0] = 0;//But instead of 0 the actual number that you want to set for the value.            
}

我希望这对你有帮助

Answer 2

我看这里没有问题。只需获取代码，编译并执行它。在为t指定值并提供t输入值之后，我在控制台上看到了一个输出

stefan@linux-3047:~$ java A
5 (t)
1 (1st of 5 values)
2 (2nd of 5 values)
3 (3rd of 5 values) 
4 (4th of 5 values) 
5 (5th of 5 values) 
0 (System.out.println)
2 (System.out.println)
6 (System.out.println)
6 (System.out.println)
6 (System.out.println)

Answer 3

这里存在多个问题

如果t for example is 5出现以下情况，则第25行出现一个错误：

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 5
    at application.A.main(A.java:25)

---

添加了一些System.out.println(...)以查看如何修复它，因为我不知道您要添加的代码：

包装申请

import java.util.*;

public class A {

    // This about finding Even Fibonacci numbers and adding them to sum.

    public static void main(String[] args) {

        System.out.println("Enter a number below:\n");
        Scanner in = new Scanner(System.in);
        int t = in.nextInt();
        System.out.println("You entered..." + t+"\n");

        // Arrays
        int[] n = new int[t];
        int[] nn = new int[t];
        int i, j, sum;

        // First For Loop
        for (int a0 = 0; a0 < t; a0++) {
            System.out.println("Enter a number a0..");
            n[a0] = in.nextInt();
            System.out.println("You entered ao=:" + a0+"\n");
        }
        nn[0] = 1;

        // Second For Loop
        for (i = 0; i < t; i++) {
            sum = 0;
            for (j = 1; j < n[i]; j++) {
                nn[j] = j + nn[j - 1];
                if (nn[j] % 2 == 0) {
                    sum += nn[j];
                }
            }

            // this is not printing the output
            System.out.println("Sum is:="+sum); 
        }
    }
}