python get majority element using divide and conquer - python-3.x

Question

your textHello can someone explain the code with sample 1 input(specially recursive call) . i am confused with these 2 recursive call lines,
left_maj = get_majority_element(a, left, mid)
right_maj = get_majority_element(a, mid, right)
Task. The goal in this code problem is to check whether an input sequence contains a majority element.
Input Format. The first line contains an integer 𝑛, the next one contains a sequence of 𝑛 non-negative
integers 𝑎0, 𝑎1, . . . , 𝑎𝑛−1.
Constraints. 1 ≤ 𝑛 ≤ 105
; 0 ≤ 𝑎𝑖 ≤ 109
for all 0 ≤ 𝑖 < 𝑛.
Output Format. Output 1 if the sequence contains an element that appears strictly more than 𝑛/2 times,
and 0 otherwise.
Sample 1.
Input:
5
2 3 9 2 2
Output:
1
2 is the majority element.
code :
import sys, math
def get_majority_element(a, left, right):
if left == right:
return -1
if left + 1 == right:
return a[left]
mid = (left + right) // 2
half_element_count = (right - left) // 2
left_maj = get_majority_element(a, left, mid)
right_maj = get_majority_element(a, mid, right)
left_maj_count = get_element_count(a, left, right, left_maj)
if left_maj_count > half_element_count:
return left_maj
right_maj_count = get_element_count(a, left, right, right_maj)
if right_maj_count > half_element_count:
return right_maj
return -1
def get_element_count(a, left, right, x):
maj_count = 0
for i in range(left, right):
if a[i] == x:
maj_count += 1
return maj_count
if __name__ == '__main__':
input = sys.stdin.read()
n, *a = list(map(int, input.split()))
if get_majority_element(a, 0, n) != -1:
print(1)
else:
print(0)
i tried to debug using pdb but got confused during recursive call