java || 3 ms ||100%faster || simplest solution
class Solution {\n    public int[] findArray(int[] pre) {\n        int[] ans=new int[pre.length];\n        ans[0]=pre[0];\n        for(int i=1;i<pre.length;i++)
# class Solution {\n    public int[] findArray(int[] pre) {\n        int[] ans=new int[pre.length];\n        ans[0]=pre[0];\n        for(int i=1;i<pre.length;i++)\n        {\n            ans[i]=pre[i-1]^pre[i];\n        }\n        return ans;\n    }\n}
['Java']