有人可以向我解释为什么此嵌套循环函数以这种方式打印吗？

Question

So here is the code that runs:

public static void main(String[] args) 
{
    for (int i=1; i<=6; i++) 
    {
        for (int j=1; j<=i; j++) 
        System.out.print("*");
        System.out.print("-");
    }
}

why does it print

*-**-***-****-*****-******-

instead of

* _ ** __ *** ___ **** ____ *****_____******______

Answer 1

this is because didnt put your print("-") inside any of your inner loops, change your loop to :

for (int i=1; i<=6; i++) 
{
    for (int j=1; j<=i; j++) 
        System.out.print("*");
    for (int j=1; j<=i; j++) 
        System.out.print("-");

}

and your problem will fix.

Answer 2

System.out.print("-"); is not inside the inner loop. Therefore it's only printed once for each iteration of the outer loop.

This becomes clearer when you indent your code properly :

for (int i=1; i<=6; i++) 
{
    for (int j=1; j<=i; j++) 
        System.out.print("*");
    System.out.print("-");
}

Even if it was inside the inner loop (by adding curly braces), you'd still not get the output you expected, since you'll get one - after each * .

In order to get the output you expected, you need two inner loops :

for (int i=1; i<=6; i++) 
{
    for (int j=1; j<=i; j++) 
        System.out.print("*");
    for (int j=1; j<=i; j++) 
        System.out.print("-");
}