Array of sword finger offer question bank summary (I) (C language version)

The finger of the sword offer Question bank summary （ One ） The array of （C Language version ）

topic 56： Two numbers that appear only once in the array

• Specific requirements of the topic ： An integer array appears only once except for two numbers , The other numbers have all appeared twice . Please write a program to find out these two numbers that only appear once .
• Data range ： The length of the array 2≤n≤1000, The size of each number in the array 0 < val ≤1000
• requirement ： Spatial complexity O(1), Time complexity O(n)
• Tips ： Output in non descending order .
  Example 1
  Input ：[1,4,1,6]
  Return value ：[4,6]
  explain ： The smaller number in the returned result comes first
• Their thinking ：
  1. General idea ： There is a problem similar to it , It refers to only one number that appears once in the array , The solution is to start from scratch and continue XOR , Because of the same two numbers, the XOR value is 0, So the final XOR result is the answer
  2. But this question has two numbers that only appear once a and b, In the end, we can only get a Exclusive or b Value , Just think about it