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Unclear, and probably homework. Try it yourself; you'll learn something.
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Hi, this questions is similar to this question, but need to return the length. I tried, but still looking for solution
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Member 11875370 wrote: I tried
Describe the algorithm you tried.
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I tried the below code, but just get the max num, to solve the leetcode question. This is the interview question I just faced today.
public int getMaxLen(int[] nums) {
int sum=nums[0];
int max=Integer.MIN_VALUE;
int result = 0;
int cnt = 0;
for(int i=1;i<nums.length;i++){
sum=Math.max(sum+nums[i],nums[i]);
max= Math.max(max, sum);
}
return result;
}
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Right, you'll need to track the "length" as you go, not just the max.
Personally, I would likely define a structure that holds the starting position, the length, and the sum.
I'd fill one with a sequence and then compare with my last known largest one and swap if larger.
modified 30-Jul-15 23:29pm.
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Had you waited a few hours you could have posted this as a Friday Programming Challenge. 
modified 31-Jul-15 2:11am.
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I whipped up an implementation in C last night. About an hour's effort.
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Sorry for my English. 
_____________________
I can't find an algorithm for this special type of bin packing problem: 
____________________
Consider a warehouse with a number of shelves that have number, width, height, depth and limit Weight capacity.
The objects that place in this warehouse are a number of cubes that have number, length, width, height and weight.
The algorithm must find the right place for objects that have the lowest waste of space. and objects weight not be more than shelf weight capacity.
** If a place was assigned to an object, back, front, and on it can not be allocated.
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Thank you.
Yes It is 3D Bin Packing, too.
But here:
1) We have several shelves.
2) If a place for an object was assigned, we can't put any objects on it, in front of it or in back.(just left side or right side is true)
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Then you need to go and read some of the information in those links that Google provided.
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funny!
what is wrong with you?
simply you can don't answer to me
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That's a nice way of saying "thank you".
If there was an answer readily available, we would not have to write so much code. If you can do the procedure for one shelf, you can do it for multiple shelves.
So, where is the problem? 
Bastard Programmer from Hell 
If you can't read my code, try converting it here[^]
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Try to write it as an integer linear programming model, it can be solved directly (maybe not efficiently, it depends) and it helps other people understand exactly what your problem looks like so we're sure we're all talking about the same problem.
If you have that, I'll gladly take a look at it.
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This is not a 3D packing problem !
If you want to optimize the warehouse usage, you need to choose if you want to minimize wasted space or wasted weight.
an algo:
sort the cubes from biggest to smallest.
for each cube
Select available places
place the cube at the place which waste minimum
next
if your problem allow to put more than 1 cube in a place which is not stated), then it is 3D packing
Patrice
“Everything should be made as simple as possible, but no simpler.” Albert Einstein
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Thank you very much
This is my answer
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public static string placeItemInBin(Item itemToPlacing)
{
LinkedListNode<Bin> binNode;
bool isPlaced = false;
int allSideStates = 1;
while (allSideStates <= 2)
{
binNode = listOfBins.First;
while (isPlaced == false && binNode != null)
{
if (binNode.Value.RemainWidth >= itemToPlacing.Width)
if (binNode.Value.RemainWeight >= itemToPlacing.Weight
&& binNode.Value.Height >= itemToPlacing.Height
&& binNode.Value.Depth >= itemToPlacing.Depth)
{
LinkedListNode<Partirion> partitionNode;
LinkedListNode<Partirion> Best;
Best=null;
partitionNode = binNode.Value.parts.First;
while (partitionNode != null)
{
if (partitionNode.Value.num == -1
&& partitionNode.Value.size >= itemToPlacing.Width
&& (Best == null || partitionNode.Value.size <= Best.Value.size))
{
Best = partitionNode;
if (Best.Value.size == itemToPlacing.Width)
break;
}
partitionNode = partitionNode.Next;
}
if (Best != null)
{
Partirion newPart = new Partirion(itemToPlacing.Width, itemToPlacing.Number,
Best.Value.cmBegin);
Best.Value.cmBegin += itemToPlacing.Width;
Best.Value.size -= itemToPlacing.Width;
binNode.Value.parts.AddBefore(Best, newPart);
itemToPlacing.BinNumber = binNode.Value.Number;
binNode.Value.RemainWidth -= itemToPlacing.Width;
binNode.Value.RemainWeight -= itemToPlacing.Weight;
binNode.Value.RemainVolume -= itemToPlacing.Width
* binNode.Value.Height * binNode.Value.Depth;
isPlaced = true;
return ("item: (" + itemToPlacing + ") ====> Bin: (" + binNode.Value + ")");
}
}
binNode = binNode.Next;
}
itemToPlacing.changeSideState();
allSideStates++;
}
return "Not Found";
}
modified 23-Jul-15 1:00am.
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Patrice
“Everything should be made as simple as possible, but no simpler.” Albert Einstein
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Now you investigate to see what gives the best solution
- no sort of cubes
- sort from biggest to smallest
- sort from smallest to biggest
Patrice
“Everything should be made as simple as possible, but no simpler.” Albert Einstein
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Thanks ![Rose | [Rose]](https://codeproject.global.ssl.fastly.net/script/Forums/Images/rose.gif)
Yes; Best way is here:
LinkBinsOrItems.sortItemList();
LinkBinsOrItems.sortBinList();
Best Sort Mode:
private void btnBestMode_Click(object sender, EventArgs e)
{
if (LinkBinsOrItems.listOfBins == null)
{
if (LinkBinsOrItems.listOfItems == null)
{
MessageBox.Show("Item List And Also Bin List Are Empty!!"
+"You Must Enter Bins And Items..."
, "Bin List And Item list Empty Error", MessageBoxButtons.OK
, MessageBoxIcon.Information);
return;
}
MessageBox.Show("Bin List Is Empty!! You Must Enter Bins...", "Bin List Empty Error"
, MessageBoxButtons.OK, MessageBoxIcon.Information);
return;
}
if (LinkBinsOrItems.listOfItems == null)
{
MessageBox.Show("Item List is Empty!! You Must Enter Items..."
, "Item List Empty Error", MessageBoxButtons.OK, MessageBoxIcon.Information);
return;
}
DialogResult result = MessageBox.Show("Are you sure you want to do sorting "
+"for creat more free space?(This can change items places"
, "Sort For Best Mode",MessageBoxButtons.YesNo,MessageBoxIcon.Question);
if (result == DialogResult.No)
return;
LinkedListNode<Item> itemNode;
LinkedListNode<Bin> binNode;
itemNode = LinkBinsOrItems.listOfItems.First;
for (int i = 1; i <= LinkBinsOrItems.listOfItems.Count; i++)
{
itemNode.Value.BinNumber = -1;
}
binNode = LinkBinsOrItems.listOfBins.First;
for (int i = 1; i <= LinkBinsOrItems.listOfBins.Count; i++)
{
binNode.Value.clearRelations();
}
LinkBinsOrItems.sortItemList();
LinkBinsOrItems.sortBinList();
listBox1.Items.Add("");
itemNode = LinkBinsOrItems.listOfItems.First;
for (int i = 1; i <= LinkBinsOrItems.listOfItems.Count; i++)
{
listBox1.Items.Add(itemNode.Value);
listBox2.Items.Add(LinkBinsOrItems.placeItemInBin(itemNode.Value));
itemNode = itemNode.Next;
}
itemReportInitaling();
BinReportInitaling();
}
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Cenator wrote: Thanks [Rose]
Thank you.
CP have a standard way to reward contributors: click on the green arrow on left of the useful answer/advice. the author is rewarded with reputation points and you also gain some organizer points.
--------------------------------------------
Depending on reality of the problem size of the warehouse and number of cubes to fit, you may want to optimize the answer even further.
Patrice
“Everything should be made as simple as possible, but no simpler.” Albert Einstein
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I wasn't sure if this forum was the best one for this question, so I apologize in advance if it isn't.
I'm currently learned Gene Expression Programming and I'm a little unclear as to how the mutation rate is applied to a population. I've looked at source code from different implementations and I've seen it used different ways and would like to know if there is actually a proper way to implement it or if it can be implement at the programmers discretion.
As an example, say there are 10 chromosomes, each with 2 genes, and each gene has 10 nodes and the mutation rate (mr) is 0.1. I've seen code that mutates nodes implemented in these way:
- Loop through each chromosome and generate a random number (rn) between 0 - 1 on each loop. If the rn <= mr then select the gene for mutation. Then loop through every node of the chromosome, ignoring gene boundaries (so in this example there are 20 nodes = 10 nodes/gene * 2 genes) and generate another rn and if the rn <= mr, mutate the node.
- Loop through each chromosome and generate a random number (rn) between 0 - 1 on each loop. If the rn <= mr then select the gene for mutation. Then loop through each gene, again generating a rn on each loop, and if the rn <= mr select the gene for mutation, otherwise continue the loop. If the gene is selected for mutation, loop through each node of the selected gene (10 nodes since there are 10 nodes/gene), generating a rn on each loop and mutate the selected node if rn <= mr.
- Randomly select 10% of the nodes in the entire populate (in this case 20 nodes since there are 200 nodes = 10 chromosomes * 2 genes/chromosome * 10 nodes/gene).
- Randomly select 10% of the chromosomes (in this case 1 chromosome) and then select the nodes for mutation following the same procedure as Item 1 or Item 2 above, starting from the second loop.
I believe that either Item 1 or Item 2 would be the correct way to apply the mutation operator, but I haven't been able to find a definitive answer either through searches on Google/CP or in the book I have been reading.
One other thing that is mentioned in the book I am reading, but isn't explained in detail is the following: there is a population of 10 chromosomes, each with 1 gene, and a total length of 14 nodes. The book states that the mutation rate should be equivalent to two one-point mutations per chromosome, which in this case (because the chromosome's length is 14) should be 0.143. How was a mr of 0.143 derived from the chromosome length of 14? This isn't explained anywhere so far, even though this equivalence has been mentioned multiple times.
Any information, or links to answers, would be greatly appreciated. Thank you in advance for any help.
A black hole is where God tried to divide by zero.
There are 10 kinds of people in the world; those who understand binary and those who don't.
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IMHO the type of mutation doesn't matter that much. Its purpose is to "jump" to nearby areas in the problem space. Any variation will accomplish that. The best mutation rate can't be stated as a hard and fast rule, as in that book; it will depend on the specific problem you're trying to solve.
(BTW, there's no "singularity" at the center of a black hole; the "infinite density" is an artifact of using continuous equations to describe a discrete system. The physicists have mistaken their equations for the reality they're trying to model.)
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