Method and device in nodes used for wireless communication

A second node for wireless communications, comprising:

• a second transmitter, transmitting a second signal;
• and
• a second receiver, receiving a first signal in a target radio resource pool, the first signal carrying a third bit block and a fourth bit block;
• wherein a first bit block is associated with the second signal;
• a second bit block corresponds to a target index, the target index is a first index or a second index, and the first index is different from the second index;
• the third bit block is related to the first bit block, and the fourth bit block is related to the second bit block;
• a determination method of the target radio resource pool is related to the target index.

A method in a first node for wireless communications, comprising:

• receiving a second signal;
• and
• transmitting a first signal in a target radio resource pool, the first signal carrying a third bit block and a fourth bit block;
• wherein a first bit block is associated with the second signal;
• a second bit block corresponds to a target index, the target index is a first index or a second index, and the first index is different from the second index;
• the third bit block is related to the first bit block, and the fourth bit block is related to the second bit block;
• a determination method of the target radio resource pool is related to the target index.