java中的偶数三角形

我怎么能用偶数和空格做同样的三角形呢？。我如何能够不受任何限制地生成偶数，并适应用户输入的行数（用户只输入行数，但不限制生成偶数或奇数）

我想要什么，但他怎么能做到

     2
    4 6
  8 10 12
14 16 18 20

---

若我理解正确，这很容易，但在数字5之后，数字将相互传递，所以若你们想避免这种情况，你们必须为你们打印的每个数字使用2或3个空格。主三角形可以通过以下方式创建：

public static void main(String[] args) {
    Scanner in = new Scanner(System.in);
    int row = in.nextInt();
    int allSpace = 2 * row - 1;
    for (int i = 1; i <= row; i++) {
        int allNumber = 2 * i - 1;
        for (int j = 0; j < (allSpace - allNumber) / 2; j++) {
            System.out.print("   ");
        }
        for (int j = 1; j <= allNumber ; j++) {
            System.out.printf("%3d", j);
        }
        for (int j = allNumber - 1; j >= i ; j--) {
            System.out.printf("%3d", j);
        }
        System.out.println();
    }
}

publicstaticvoidmain（字符串[]args）{
扫描仪输入=新扫描仪（系统输入）；
int row=in.nextInt（）；
int allSpace=2*行-1；
对于（inti=1；i，这有点棘手，因为数字的数量会稍微影响对齐

这将有助于：

    int num = 5;
    int cont = 0;
    for (int i = 1; i <= num; i++) {
        for(int k = 1; k <= num -i; k++) System.out.print(" ");
        for(int j = 1; j <= i; j++) {
            cont += 2;
            System.out.print(cont + " ");
        }

    System.out.println ("");
    }

int num=5；
int cont=0；
对于（inti=1；i这将得到您想要的结果

    int rows = 500;

    //Calculating the largest number we will reach:
    int largest = 1;
    for(int i=1;i<=rows;i++){  

        largest=largest + i;    
    } 
    largest=largest*2;//since we only count even numbers


    int cur = 2; //current value to add to the triangle
    int rowsize = 0; //how many values to fit inside the row

    for (int i = 1; i <= rows; i ++) {

        int cursize = 0; //ammount of values currently in the row

        //filling spaces on left side
        //The value is based on how many rows we want, more rows = need for more initial spacing
        String spaces = "";
        for(int j = 0 ; j < (rows + "").length() ; j++) {
            spaces += " ";
        }
        for (int j = 0; j <= rows - i ; j++) {

            System.out.print(spaces);
        }

        while(cursize <= rowsize) {

            //For each number, we calculate how much spacing to place before it
            int len = (largest + "").length() - (cur + "").length();
            spaces = "";
            while(len != 0) {
                spaces += " ";
                len--;
            }

            System.out.print(" " + spaces + cur);
            cur += 2;
            cursize++;

        }

        System.out.println (""); //new line
        rowsize++;
    }
}

int行=500；
//计算我们将达到的最大数量：
int最大=1；
对于（int i=1；i
int number=2；
对于（int row=1；row），它表示必须在每行中打印多少值
数字-->它是将要打印的实际值
您是否尝试过自己解决这个问题？
public static void main(String[] args) {
    Scanner in = new Scanner(System.in);
    int row = in.nextInt();
    int allSpace = 2 * row - 1;
    int even = 2;
    for (int i = 1; i <= row; i++) {
        int allNumber = 2 * i - 1;
        for (int j = 0; j < (allSpace - allNumber) / 2; j++) {
            System.out.print("   ");
        }
        for (int j = 1; j <= allNumber ; j++) {
            System.out.printf("%3d", even);
            even += 2;
        }
        System.out.println();
    }
}

    int num = 5;
    int cont = 0;
    for (int i = 1; i <= num; i++) {
        for(int k = 1; k <= num -i; k++) System.out.print(" ");
        for(int j = 1; j <= i; j++) {
            cont += 2;
            System.out.print(cont + " ");
        }

    System.out.println ("");
    }

    int rows = 500;

    //Calculating the largest number we will reach:
    int largest = 1;
    for(int i=1;i<=rows;i++){  

        largest=largest + i;    
    } 
    largest=largest*2;//since we only count even numbers


    int cur = 2; //current value to add to the triangle
    int rowsize = 0; //how many values to fit inside the row

    for (int i = 1; i <= rows; i ++) {

        int cursize = 0; //ammount of values currently in the row

        //filling spaces on left side
        //The value is based on how many rows we want, more rows = need for more initial spacing
        String spaces = "";
        for(int j = 0 ; j < (rows + "").length() ; j++) {
            spaces += " ";
        }
        for (int j = 0; j <= rows - i ; j++) {

            System.out.print(spaces);
        }

        while(cursize <= rowsize) {

            //For each number, we calculate how much spacing to place before it
            int len = (largest + "").length() - (cur + "").length();
            spaces = "";
            while(len != 0) {
                spaces += " ";
                len--;
            }

            System.out.print(" " + spaces + cur);
            cur += 2;
            cursize++;

        }

        System.out.println (""); //new line
        rowsize++;
    }
}

int number=2;
for(int row=1;row<=4;row++) {
    for(int space=1;space<=(4-row);space++) {
        System.out.print(" ");
    }
    for(int noOfValue=1;noOfValue<=row;noOfValue++) {
        System.out.print(number+" ");
        number=number+2;
    }
    System.out.println();
}