[JAVA} Need help in a Nested Loop

[conrey]

Any1 can help me in java that can will have an output like these please..

54321
4321
321
21
1

Ive tried all my best but still my code gives like infinite loop or something..

conrey Reviewed by conrey on 10th Sep 2011. [JAVA} Need help in a Nested Loop Any1 can help me in java that can will have an output like these please.. 54321 4321 321 21 1 Rating: 5

[busylife007]

123456
12345
1234
123
12
1

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

source :

http://www.roseindia.net/answers/vie...-Question.html

[Nitish]

Though busylife already did it but if you want the code to generate exact same output which you wanted, then here it is:

class nitish{
public static void main (String args[]) {


for (int i = 5; i >=0; i--) {
for (int j = i; j > 0; j--) {
System.out.print(j);
}
System.out.println();
}
}
}

[conrey]

123456
12345
1234
123
12
1

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

source :

http://www.roseindia.net/answers/vie...-Question.html

sorry mate I don't mean that output..but thanks anyways..

@Nitish

thank you so much bro.

[Nitish]

Your most welcome. If you need any further java help, then you can directly PM me

[conrey]

sure I'll always remember it bro...

if its ok can you please xplain how does the code really works? I mean the difference of the outer for loop and the inner for loop?

[Nitish]

or (int i = 5; i >=0; i--) {
for (int j = i; j > 0; j--) {
System.out.print(j);
}
System.out.println();
}

This is your code.
You have 2 variables, i and j.
Try placing yourself in place of compiler. Write i and j on register.
Now its written , int i=5. That means "i" is an integer with value 5 assigned to it and if you know the syntax of "FOR" loop, second condition limits the value and third conditions proceeds the loop.
So, coming in the nested loop, where j is equal to 5.
So, next line is printing j.
So we write the value of j on the register which is equal to 5 and just before that we check the condition(j>0 ?? yes? ok, proceed)
So your register has
5 written on it.
now, j-- . so j is 4. check again, is j>0? yes? ok, proceed,
54
now, j=3. check again..
543
now j =2, check again, ..
5432..
now, j=1, check agian..
54321
now j=0 , check, no? come out of the loop.
println() means taking the cursor to next line.
now i--.
so i=4.
and j =i therefore j=4.
and again start with printing j and checking..
so it will be
54321
4
then 54321
43... and so on. this is how program will work in very lay man's terms.

[Apathetic]

public class apathetic{
	public static void main(String[] args){
		for(int a=5;a>0;a--){
			for(int b=a;b>0;b--){
				System.out.print(b);
			}
		System.out.println();
		}
	}
}

When doing nested loops, create the inner loop first then go for the outer loop

[conrey]

or (int i = 5; i >=0; i--) {
for (int j = i; j > 0; j--) {
System.out.print(j);
}
System.out.println();
}

This is your code.
You have 2 variables, i and j.
Try placing yourself in place of compiler. Write i and j on register.
Now its written , int i=5. That means "i" is an integer with value 5 assigned to it and if you know the syntax of "FOR" loop, second condition limits the value and third conditions proceeds the loop.
So, coming in the nested loop, where j is equal to 5.
So, next line is printing j.
So we write the value of j on the register which is equal to 5 and just before that we check the condition(j>0 ?? yes? ok, proceed)
So your register has
5 written on it.
now, j-- . so j is 4. check again, is j>0? yes? ok, proceed,
54
now, j=3. check again..
543
now j =2, check again, ..
5432..
now, j=1, check agian..
54321
now j=0 , check, no? come out of the loop.
println() means taking the cursor to next line.
now i--.
so i=4.
and j =i therefore j=4.
and again start with printing j and checking..
so it will be
54321
4
then 54321
43... and so on. this is how program will work in very lay man's terms.

thank you so much bro..

@apathetic

can you please tell me why is it good to first make the inner loop first??

[Lock Down]

The inner loop causes the numbers to print without the line break so it starts with highest to lowest.

The outer loop subtracts 1 from the highest and causes a line break.