# 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]

**Pictorial Presentation:**

**Sample Solution-1:**

**Python Code:**

```
#License: https://bit.ly/3oLErEI
def test(nums, sep):
ans = [sep] * (2 * len(nums) - 1)
ans[::2] = nums
return ans
nums = [12, -7, 3, -89, 14, 88, -78, -1, 2, 7]
separator = 6
print("List of numbers:",nums)
print("Separator:",separator)
print("Inject the separator in between each pair of adjacent numbers of the said list:")
print(test(nums,separator))
nums = [1, 2, 3, 4, 5, 6]
separator = 9
print("\nList of numbers:",nums)
print("Separator:",separator)
print("Inject the separator in between each pair of adjacent numbers of the said list:")
print(test(nums,separator))
```

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
def test(nums, sep):
result = []
for i in range(len(nums)):
if i == len(nums) - 1:
result.append(nums[i])
else:
result.append(nums[i])
result.append(sep)
return result
nums = [12, -7, 3, -89, 14, 88, -78, -1, 2, 7]
separator = 6
print("List of numbers:",nums)
print("Separator:",separator)
print("Inject the separator in between each pair of adjacent numbers of the said list:")
print(test(nums,separator))
nums = [1, 2, 3, 4, 5, 6]
separator = 9
print("\nList of numbers:",nums)
print("Separator:",separator)
print("Inject the separator in between each pair of adjacent numbers of the said list:")
print(test(nums,separator))
```

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]

**Python Code Editor :**

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