To determine how many people came to Janet's concert on the third night, follow these steps:
1. Calculate the number of people who came on the second night.
\( \text{People on first night} = 1256 \)
\( \text{Difference between first and second night} = 362 \)
\[
\text{People on second night} = 1256 - 362 = 894
\]
2. Calculate the total number of people who came on the first two nights.
\[
1256 + 894 = 2150
\]
3. Subtract the number of people who came on the first two nights from the total number of attendees over three nights to find out how many people came on the third night.
\( \text{Total number of people over three nights} = 2712 \)
\[
\text{People on third night} = 2712 - 2150 = 562
\]
So, the number of people who came on the third night is \( 562 \).