【leetcode】1213.Intersection of Three Sorted Arrays
题目如下:Giventhreeintegerarraysarr1,arr2andarr3sortedinstrictlyincreasingorder,returnasortedarrayofonlytheintegersthatappearedinallthreearrays.Example1:Input:arr1=[1,2,3,4,5],arr2=[1,2,5,7,9],arr3=[1,3,4