the reference answer GPT ᴼ ᴾ ᴱ ᴺ ᴬ ᴵ < br / > in 3 color ZK certificate, if the certificate is not upset color in each iteration, the agreement will no longer be zero knowledge.
The reason is that the core concept of zero-knowledge protocol is that the prover can only disclose the necessary information to the verifier, and not disclose any other information about the secret. In the ZK proof of 3 coloring, the prover needs to select a different color in each iteration and color it to show its legal coloring with coloring graph. If the prover insists on using the same color arrangement in each iteration, the prover will be able to infer that color arrangement based on the prover's coloring information, and thus learn more about the coloring diagram.
Therefore, if the prover does not scramble the colors in each iteration, the protocol is no longer zero-knowledge. To ensure the zero-knowledge nature of the protocol, the prover needs to rearrange the colors in each iteration so that the verifier cannot determine the color arrangement.