'Generate all contiguous sequences from an array

There's an array say [1,2,4,5,1]. I need to print all the contiguous sub-arrays from this.

Input: [1,2,4,5,1]

Output:

 1
 1,2
 1,2,4
 1,2,4,5
 1,2,4,5,1
 2
 2,4
 2,4,5
 2,4,5,1
 4
 4,5
 4,5,1
 5
 5,1
 1

I tried but couldn't get the complete series.

//items is the main array
for(int i = 0; i < items.length; i++) {
    int num = 0;
    for(int j = 0; j < items.length - i; j++) {
        for(int k = i; k < j; k++) {
            System.out.print(items[k]);
        }
        System.out.println();
    }
}
javaarrayslogic


Solution 1:[1]

You only have to make 2 changes. The outer loop iterates as much times as the array has elements, this is correct. The first inner loop should use the index of the outer loop as start index (int j = i), otherwise you always start with the first element. And then change the inner loop break conditon to k <= j, otherwise i does not print the last element. 

// i is the start index
for (int i = 0; i < items.length; i++)
{
    // j is the number of elements which should be printed
    for (int j = i; j < items.length; j++)
    {
        // print the array from i to j
        for (int k = i; k <= j; k++)
        {
            System.out.print(items[k]);
        }
        System.out.println();
    }
}

Solution 2:[2]

Tested and working! Try this algorithm.

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

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

            for(int k=i;k<=j;k++) {

                System.out.print(items[k]);
            }
            System.out.println();
        }
}

Solution 3:[3]

The problem seems to be with your second loop:

for(int j=0;j<items.length-i;j++)

You're always running on the first i places. What you want to do is run from i until the end of the array, as such:

for(int j=i;j<items.length;j++)

Solution 4:[4]

I think this may help 

for(int i=0;i<=items.length-1;i++)
{
    for(int l=i;l<=items.length;l++)
    {
    int b[]=Arrays.copyOfRange(a, i,l);

        for(int k=0;k<=b.length-1;k++)
        {
            System.out.print(b[k]);
        }

        System.out.println();
    }
}

Solution 5:[5]

Try this way. 

int items[]={1,2,4,5,1};
for(int i=0;i<=items.length;i++)//items is the main array 
{
    int num=0;
    for(int j=0;j<items.length;j++)
    {
        for(int k=i;k<=j;k++)
        {
            System.out.print(items[k]);
        }

        System.out.println();
    }
}

Solution 6:[6]

Use the below code:

import java.io.*;
class stack
{
    public static void main(String args[]) throws IOException
    {
        int items[]={1,2,4,5,1};

        for(int i=0;i<items.length;i++)//items is the main array 
        {
            for(int j=i;j<items.length;j++)
            {
                for(int k=i;k<=j;k++)
                {
                    System.out.print(items[k]);
                    if (k==j)
                        continue;
                    else
                        System.out.print(",");
                }
                System.out.println();
            }
        }
    }
}

Solution 7:[7]

// Javascript.
// Generate Array and print it.
function subArray(arr) {
    if (arr.length < 1) return 0;
    if (arr.length < 2) return arr[0];

    let result = [];
    for (let i = 0; i < arr.length; i++) {
        const temp = [];
        for (let j = i; j < arr.length; j++) {
            temp.push(arr[j]);
            result.push([...temp]);
            console.log(temp.join(','));
        }
    }
    return result
}

// Calculate only Sum of the subarrays.
function subArrSum(arr) {
  if (arr.length < 1) return 0;
  if (arr.length < 2) return arr[0];

  let sum = 0;
  for (let i = 0; i < arr.length; i++) {
      sum += (arr.length - i) * (i + 1) * arr[i];
  }
  return sum;
}

Solution 8:[8]

There is one better approach that takes less time:

Input:

int items[] = {1,2,3,4};

Code:

int j = 0;
StringBuilder sb = new StringBuilder();

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

   sb.setLength(0);
   j = 0;
   sb.append(items[i]+ " ");
   System.out.print(sb.toString()+ " ");
   System.out.println();

   j=i+1;
   
   while(j< items.length){

       sb.append(arr.get(j) + " ");
       System.out.print(sb.toString() +" ");
       System.out.println();

       j = j+1;
   }
   System.out.println();
   }

Output:

  1
  1 2
  1 2 3
  1 2 3 4

  2 
  2 3
  2 3 4
  
  3
  3 4

  4

Solution 9:[9]

def printSubsequences(l, r, arr:list, n):

if(l == n):
    return
while(l<=r):
    print(arr[l:r+1])
    r-=1
printSubsequences(l+1, n-1, arr, n)

if __name__ == "__main__":
arr = list(map(int, input("Enter : ").strip().split()))
printSubsequences(0, len(arr)-1, arr, len(arr))

Solution 10:[10]

Try something like this:

for(int i=0; i<items.length; i++)
{
   for(int j=i; j<items.length; j++)
   {
      System.out.print(items[j]);
   }
   System.out.println();
}

I haven't tested yet, but it should work.

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