# Python: Inject a number in between each pair of adjacent numbers in a list of numbers

## Python Programming Puzzles: Exercise-71 with Solution

Given a list of numbers and a number to inject, write a Python program to create a list containing that number in between each pair of adjacent numbers.

Input: [12, -7, 3, -89, 14, 88, -78, -1, 2, 7] Separator: 6 Output: [12, 6, -7, 6, 3, 6, -89, 6, 14, 6, 88, 6, -78, 6, -1, 6, 2, 6, 7] Input: [1, 2, 3, 4, 5, 6] Separator: 9 Output: [1, 9, 2, 9, 3, 9, 4, 9, 5, 9, 6]

**Visual Presentation:**

**Sample Solution-1:**

**Python Code:**

```
# License: https://bit.ly/3oLErEI
# Define a function named 'test' that takes a list of numbers and a separator as input
def test(nums, sep):
# Initialize a list 'ans' with double the length of 'nums' minus one, filled with separators
ans = [sep] * (2 * len(nums) - 1)
# Replace every second element of 'ans' with the corresponding elements from 'nums'
ans[::2] = nums
return ans # Return the modified list
# Example 1
nums1 = [12, -7, 3, -89, 14, 88, -78, -1, 2, 7]
separator1 = 6
print("List of numbers:", nums1)
print("Separator:", separator1)
print("Inject the separator in between each pair of adjacent numbers of the said list:")
print(test(nums1, separator1))
# Example 2
nums2 = [1, 2, 3, 4, 5, 6]
separator2 = 9
print("\nList of numbers:", nums2)
print("Separator:", separator2)
print("Inject the separator in between each pair of adjacent numbers of the said list:")
print(test(nums2, separator2))
```

Sample Output:

List of numbers: [12, -7, 3, -89, 14, 88, -78, -1, 2, 7] Separator: 6 Inject the separator in between each pair of adjacent numbers of the said list: [12, 6, -7, 6, 3, 6, -89, 6, 14, 6, 88, 6, -78, 6, -1, 6, 2, 6, 7] List of numbers: [1, 2, 3, 4, 5, 6] Separator: 9 Inject the separator in between each pair of adjacent numbers of the said list: [1, 9, 2, 9, 3, 9, 4, 9, 5, 9, 6]

**Flowchart:**

**Sample Solution-2:**

**Python Code:**

```
# License: https://bit.ly/3oLErEI
# Define a function named 'test' that takes a list of numbers and a separator as input
def test(nums, sep):
result = [] # Initialize an empty list to store the result
# Iterate through the indices of 'nums'
for i in range(len(nums)):
# Check if the current index is the last one
if i == len(nums) - 1:
result.append(nums[i]) # If it is the last index, append the number without the separator
else:
result.append(nums[i]) # Append the current number to the result
result.append(sep) # Append the separator after the current number
return result # Return the modified list
# Example 1
nums1 = [12, -7, 3, -89, 14, 88, -78, -1, 2, 7]
separator1 = 6
print("List of numbers:", nums1)
print("Separator:", separator1)
print("Inject the separator in between each pair of adjacent numbers of the said list:")
print(test(nums1, separator1))
# Example 2
nums2 = [1, 2, 3, 4, 5, 6]
separator2 = 9
print("\nList of numbers:", nums2)
print("Separator:", separator2)
print("Inject the separator in between each pair of adjacent numbers of the said list:")
print(test(nums2, separator2))
```

Sample Output:

List of numbers: [12, -7, 3, -89, 14, 88, -78, -1, 2, 7] Separator: 6 Inject the separator in between each pair of adjacent numbers of the said list: [12, 6, -7, 6, 3, 6, -89, 6, 14, 6, 88, 6, -78, 6, -1, 6, 2, 6, 7] List of numbers: [1, 2, 3, 4, 5, 6] Separator: 9 Inject the separator in between each pair of adjacent numbers of the said list: [1, 9, 2, 9, 3, 9, 4, 9, 5, 9, 6]

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