Check to see if an array is sorted

[ToN10]

Hey guys,

Ok, basically, I had to copy an array of integers that another class sent to mine, and then do various things to it. The final thing I have to do is have the method sorted() check the array (localArray) to see whether or not it is sorted. (Ascending and Descending both count as sorted, no order what-so-ever doesnt.) The method then returns true if it is sorted, and false if it is not sorted. I sounds so simple for me, but I'm not sure why this isnt working. Here is the code I wrote:


public boolean sorted( ){
for(int i=0;i<50;i++){
if(localArray<localArray[i+1]){
return true;}
else if(localArray>localArray[i+1]){
return true;}
else{
return false;} //by this point, the return statement should be set.
}
//compiler wants a return statement here(apparently the set statment above does not count.
}

Any idea's? Thanks.

 

[LFI]

Using your code:

public boolean sorted( ){
 boolean ascending = false;
 int first = localArray[0];
 int second = localArray[1];
 if(second > first) //ascending
  ascending = true;

 for(int i=1; i<49; i++) //note:  assumes [49] is last index
 {
  if((ascending && localArray[i] > localArray[i+1]) || (!ascending && localArray[i] < localArray[i+1]))
   return false;
 }

 return true;
}

If it fails the test one time, it returns false. If it passes through the for-loop without returning false, it returns true.

Is this what you're after?

Dave


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
O Time, Strength, Cash, and Patience!

 

[Diancecht]

Just a hint. If you plan to sort the array if it's not already sorted, I think it's easier to order it anyway.

If it's already ordered, the operation will be really low cost.

Cheers,
Dian

 

[ToN10]

thanks Dave, that works! i definitely would have never guessed to do it like that, but i can see how it works, and how mine was never going to work like it was. thanks again.

and dian, i actually did not want to sort it, so yeah. thanks for the reply though.

good forums.

 

[LFI]

'glad that did it for you!

Have a great day!

Dave


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
O Time, Strength, Cash, and Patience!