for loop in java

[newjava]

Hi,
I am new here and beginner for java.
I wrote a simple List program with for loop.

public class UserDemo {

List<String> userNameList = new ArrayList<String>();

public UserDemo (int number, String prefix){
for(int i =1; i <= number; i++){
addUser(prefix +"."+ i);
}
System.out.println("User :" +userNameList );

int size = userNameList.size();
for(int i=0; i<size-1; i++ ){
for(int j=i; j<size-1; j++){
makeFriend(userNameList.get(i),
userNameList.get(j+1));
}
}
}

public void addUser (String username){
userNameList.add(username);
}

public void makeFriend (String currentUsername, String
previousUsername){
System.out.println(currentUsername + " is friend of-> "
+previousUsername);
}

public static void main(String[] args) {
UserDemo au = new UserDemo(5,"newjava");
}
}

After running this code i m getting output in this form

User :[newjava.1, newjava.2, newjava.3, newjava.4, newjava.5]
newjava.1 is friend of-> newjava.2
newjava.1 is friend of-> newjava.3
newjava.1 is friend of-> newjava.4
newjava.1 is friend of-> newjava.5
newjava.2 is friend of-> newjava.3
newjava.2 is friend of-> newjava.4
newjava.2 is friend of-> newjava.5
newjava.3 is friend of-> newjava.4
newjava.3 is friend of-> newjava.5
newjava.4 is friend of-> newjava.5


but i want output in this form

User :[newjava.1, newjava.2, newjava.3, newjava.4, newjava.5]
newjava.1 is friend of-> newjava.2
newjava.1 is friend of-> newjava.3
newjava.1 is friend of-> newjava.4
newjava.1 is friend of-> newjava.5

newjava.2 is friend of-> newjava.1
newjava.2 is friend of-> newjava.3
newjava.2 is friend of-> newjava.4
newjava.2 is friend of-> newjava.5

newjava.3 is friend of-> newjava.1
newjava.3 is friend of-> newjava.2
newjava.3 is friend of-> newjava.4
newjava.3 is friend of-> newjava.5

newjava.4 is friend of-> newjava.1
newjava.4 is friend of-> newjava.2
newjava.4 is friend of-> newjava.3
newjava.4 is friend of-> newjava.5

newjava.5 is friend of-> newjava.1
newjava.5 is friend of-> newjava.2
newjava.5 is friend of-> newjava.3
newjava.5 is friend of-> newjava.4

Please help me that what to write within for loop, so it will give output
as mentioned.

Thanks in advance!

[masijade]

Then don't use j=i+1, and don't use size - 1, and don't use get(j+1). Use j=0, size, if (j == i) continue, and get(j).

[Krooger]

Your going to want to try something like:

   int size = userNameList.size();
   for(int i=0; i<size-1; i++ ) {
      for(int j=0; j<size-1; j++){ 
         if (i!=j)
            makeFriend(userNameList.get(i), userNameList.get(j));
      }
   System.out.println();
   }

Also try to use code blocks, makes reading easier.

[masijade]

   int size = userNameList.size();
   for(int i=0; i<size-1; i++ ) {
      for(int j=0; j<size-1; j++){ 
         if (i!=j)
            makeFriend(userNameList.get(i), userNameList.get(j));
      }
   System.out.println();
   }

What about the last elements in the list?

And there is no reason to do it for him.

[Krooger]

Oh yes, use size NOT size-1, good call... Sleeeepy

[newjava]

Ahhaa!! Its working now... Thank u very much Masijade & Krooger,
From next time i'll take care to use Code block...

[deepakbatham007]

U can also use below [CODE]

for (int i = 0; i < size; i++) {
for (int j = 0; j < size; j++) {
if (i != j) {
makeFriend(userNameList.get(i), userNameList.get(j));
}
}
}

[masijade]

:sigh: double :sigh: