Can anyone explain me what is happening in the I and j loops?

Question

public class Program
{static void pattern(String n){
int c=0; String s="";
String a="";
for(int i=-1;i<n.length();i++){
c++;

for(int j=n.length()-1;j>n.length()-c;j--){
s=(n.charAt(j)+""+n.charAt(i));
a=""+s;
}

System.out.print (a);;

}

System.out.print ("");}
public static void main(String[] args) {
String n="house" ;
pattern(n);
}
}

Answer 1

🅰🅹 🅐🅝🅐🅝🅣 you mean writing the answer?

Answer 2

🅰🅹 🅐🅝🅐🅝🅣 thanks for the help

Answer 3

Someone please answer

Answer 4

🅰🅹 🅐🅝🅐🅝🅣 thanks but in general -1 shows exception why not here?

Answer 5

And why j is not decremented once

Answer 6

Atul

Writing.....

Answer 7

Atul

In this code it is happening like this:

n = "house"

here i start from -1 and j start from n.length() - 1 means j = 4 till j > (5 - 1)

So for i = -1, j = 4; j > 4 nothing will happen

now for i = 0, j = 4; j > 3
s = n.charAt(4) + ""+ n.charAt(0) = eh
a = eh

System.out.print(a) // will print eh
------------

for i = 1 Inner loop will work two times but only last value will be print

now for i = 1, j = 4, j > 2, j--
s = n.charAt(4) + "" + n.charAt(1) = eo
a = eo;

for i = 1, j = 3, j > 2, j--
s = n.charAt(3) + "" + n.charAt(1) = so

System.out.print(a) // will print so

------------------

And so on....

so finally it is ehsou and then reversing it oushe

Finally we get

ehsououshe

Answer 8

Atul

Why it will show exception? We can assign negative value too.

Answer 9

Atul

j is decrementing but depending on c variable

For 1st iteration of outer loop c will be 1 but j = 4; j > 4 so in this case j will not decrement

But after 2nd iteration of outer loop c will be 2 so inner will look like this:

for (j = 4; j > (5 - 2); j--) here j will be decrement