3. (8 points) Jia, Yi, Bing, and Ding won the top 4 places in the school (no ties), and they said:
Jia: “I am neither first nor second”; Yi said: “My rank is adjacent to Bing”;
Bing: “I am neither second nor third”; Ding: “My rank is adjacent to Yi”. Now we know that Jia, Yi, Bing, and Ding respectively obtained the $A, B, C, D$ places, and they are all honest students. So the four-digit number $\overrightarrow{\mathrm{ABCD}}=$ . $\qquad$
【Answer】Solution: According to the analysis, A is either 3rd or 4th, C is either 1st or 4th. If C is 4th, then B would be 3rd, leaving no suitable position for A. Therefore, C is 1st, B is 2nd, D is 3rd, and A is 4th. Hence, the answer is: 4213.