回複：回複：Catch and Match

n<=m+1,this clear, right? otherwise, we can find at least 3 cards one graph is identified.
By induction,n=2,m=1.n=3,m=3.
n=2t-1,m=2t-1 are right, let me see n=2t,we can creat a piece of card which sytisfied,as m is odd....
If this question is very important for you.Please write your concrete application in Chinese.Maybe I can do something for you.As this question in Math is simple.