two sum II O(n) easy

Array/TwoSumIIAlreadySorted.py

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+"""
+Given an array of integers that is already sorted in ascending order, find two numbers such that they add up to a specific target number.
+
+The function twoSum should return indices of the two numbers such that they add up to the target, where index1 must be less than index2.
+
+Note:
+
+Your returned answers (both index1 and index2) are not zero-based.
+You may assume that each input would have exactly one solution and you may not use the same element twice.
+Example:
+
+Input: numbers = [2,7,11,15], target = 9
+Output: [1,2]
+Explanation: The sum of 2 and 7 is 9. Therefore index1 = 1, index2 = 2.
+
+Two Sum 已经排序后的输出，直接可以O(n):
+
+解释传送门：
+TwoSum.
+ThreeSum.
+
+"""
+class Solution(object):
+    def twoSum(self, sortedNums, target):
+        """
+        :type numbers: List[int]
+        :type target: int
+        :rtype: List[int]
+        """
+
+        start = 0
+        end = len(sortedNums) - 1
+        while start <= end:
+            # print(nums[start] + nums[end])
+            if sortedNums[start] + sortedNums[end] == target:
+                return start+1, end+1
+
+            if sortedNums[start] + sortedNums[end] > target:
+                end -= 1
+            else:
+                start += 1
+