Python Algorithms

Remove Duplicates from a List

def remove_duplicates(nums: list) -> list:
    return list(set(nums))
    
print(remove_duplicates([1, 2, 2, 3, 4, 4, 5]))  # Output: [1, 2, 3, 4, 5]

Two Sum

The two sum algorithm works by iterating through the array and for each element, finding its complement (i.e., the other number that adds up to the target value). We use a nested loop to iterate through the remaining elements of the array and check if their sum is equal to the target value. If it is, we return the indices of both elements as the result.

def two_sum(arr, target):
    for i in range(len(arr)):
        for j in range(i+1, len(arr)):
            if arr[i] + arr[j] == target:
                return [i, j]
    return [-1, -1]

print(two_sum([2, 7, 11, 15], 9))
# Output: [0, 1]

Merge Two Sorted Lists

def merge_sorted_lists(list1: list, list2: list) -> list:
    merged = []
    i = j = 0
    while i < len(list1) and j < len(list2):
        if list1[i] < list2[j]:
            merged.append(list1[i])
            i += 1
        else:
            merged.append(list2[j])
            j += 1
    merged.extend(list1[i:])
    merged.extend(list2[j:])
    return merged

print(merge_sorted_lists([1, 3, 5], [2, 4, 6]))  # Output: [1, 2, 3, 4, 5, 6]

Fibonacci Series

The Fibonacci series algorithm works by defining a recursive function that takes an integer argument n. If n is 0 or 1, we return the value of n as the result. Otherwise, we add the values of fibonacci(n-1) and fibonacci(n-2).

def fibonacci(n):
    if n <= 1:
        return n
    else:
        return fibonacci(n-1) + fibonacci(n-2)
print(fibonacci(5)) # 5