2021: Tcs Coding Questions

return None

def first_non_repeating_char(s): char_count = {} for char in s: if char in char_count: char_count[char] += 1 else: char_count[char] = 1 Tcs Coding Questions 2021

Example: Input - "aabbc", Output - "c"

for num in arr: complement = target_sum - num if complement in seen: count += 1 seen.add(num) Tcs Coding Questions 2021

Given an array of integers and a target sum, count the number of pairs with that sum. Tcs Coding Questions 2021

# Create a sample linked list: 1 -> 2 -> 3 -> 4 -> 5 head = Node(1) head.next = Node(2) head.next.next = Node(3) head.next.next.next = Node(4) head.next.next.next.next = Node(5)