Deepak - 1 year ago 293

Java Question

Merry Christmas and hope you are in great Spirits,I have a Question in Java-Arrays as shown below.Im stuck up with this struggling to get it rite.

`Consider the leftmost and righmost appearances of some value in an array. We'll say that the "span" is the number of elements between the two inclusive. A single value has a span of 1. Write a **Java Function** that returns the largest span found in the given array.`

**Example:

maxSpan({1, 2, 1, 1, 3}) → 4,answer is 4 coz MaxSpan between 1 to 1 is 4

maxSpan({1, 4, 2, 1, 4, 1, 4}) → 6,answer is 6 coz MaxSpan between 4 to 4 is 6

maxSpan({1, 4, 2, 1, 4, 4, 4}) → 6,answer is 6 coz Maxspan between 4 to 4 is 6 which is greater than MaxSpan between 1 and 1 which is 4,Hence 6>4 answer is 6.

I have the code which is not working,it includes all the Spans for a given element,im unable to find the MaxSpan for a given element.

Please help me out.

maxSpan({1, 2, 1, 1, 3}) → 4 5 X

maxSpan({1, 4, 2, 1, 4, 1, 4}) → 6 8 X

maxSpan({1, 4, 2, 1, 4, 4, 4}) → 6 9 X

maxSpan({3, 3, 3}) → 3 5 X

maxSpan({3, 9, 3}) → 3 3 OK

maxSpan({3, 9, 9}) → 2 3 X

maxSpan({3, 9}) → 1 1 OK

maxSpan({3, 3}) → 2 3 X

maxSpan({}) → 0 1 X

maxSpan({1}) → 1 1 OK

::Code::

`public int maxSpan(int[] nums) {`

int count=1;//keep an intial count of maxspan=1

int maxspan=0;//initialize maxspan=0

for(int i=0;i<nums.length;i++){

for(int j=i+1;j<nums.length;j++){

if(nums[i] == nums[j]){

//check to see if "i" index contents == "j" index contents

count++; //increment count

maxspan=count; //make maxspan as your final count

int number = nums[i]; //number=actual number for maxspan

}

}

}

return maxspan+1; //return maxspan

}

Answer Source

I see the following problems with your attempt:

Your

`count`

is completely wrong. You can instead calculate`count`

from`i`

and`j`

:`j - i + 1`

You're overriding

`maxcount`

as soon as you get*any*span, so you're going to end up with the*last*span, not the*maximum*span. Fix it by going`maxspan = Math.max(maxspan, count);`

.You can remove the line

`int number = nums[i];`

as you never use`number`

.Remove the

`+1`

in the`return`

maxspan+1;` if you follow my tips above.Initial

`maxspan`

should be 1 if there are any values in the array, but 0 if the array is empty.

That should help you get it working. Note that you can do this in a single pass of the array, but that's probably stretching it too far for you. Concentrate on getting your code to work before considering efficiency.