ASSIGNMENT 4

1.Two Sum
Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target.

CODE:

class Solution(object):
def twoSum(self, nums, target):
num_map = {}
for i, num in enumerate(nums):
complement = target - num
if complement in num_map:
return [num_map[complement], i]
num_map[num] = i

OUTPUT:
[2,7,11,15]
9
[0,1]

2.Two Sum II- Input array is sorted
Given a 1-indexed array of integers numbers that is already sorted in non-decreasing order, find two numbers such that they add up to a specific target number. Let these two numbers be numbers[index1] and numbers[index2] where 1 <= index1 < index2 <= numbers.length.

CODE:

`class Solution:
def twoSum(self, numbers, target):

    start = 0
    end = len(numbers) - 1

    while start < end:

        total = numbers[start] + numbers[end]

        if total == target:
            return [start + 1, end + 1]

        elif total < target:
            start += 1
        else:
            end -= 1

    return [-1, -1]`

OUTPUT:

[2,7,11,15]
9
[1,2]