# Python Bisect: Find the first occurrence of a given number in a sorted list using Binary Search

## Python Bisect: Exercise-4 with Solution

Write a Python program to find the first occurrence of a given number in a sorted list using Binary Search (bisect).

**Sample Solution**:

**Python Code:**

```
from bisect import bisect_left
def Binary_Search(a, x):
i = bisect_left(a, x)
if i != len(a) and a[i] == x:
return i
else:
return -1
nums = [1, 2, 3, 4, 8, 8, 10, 12]
x = 8
num_position = Binary_Search(nums, x)
if num_position == -1:
print(x, "is not present.")
else:
print("First occurrence of", x, "is present at index", num_position)
```

Sample Output:

First occurrence of 8 is present at index 4

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