## On the Subject of 16 Coins

1000011010000111...

There will be 16 coins arranged in a 4×4 square: “H” is heads, “T” is tails. Follow the steps to determine the target coin, then click it.

- Count the number of heads in the even columns (marked with an X below). If the number of heads is odd, the target coin is in an even column. Otherwise, it is in the other columns.
x x x x x x x x - Count the number of heads in the right half (marked with an X below). If the number of heads is odd, the target coin is in the right half. Otherwise, it is in the other half.
x x x x x x x x - Count the number of heads in the even rows (marked with an X below). If the number of heads is odd, the target coin is in an even row. Otherwise, it is in the other rows.
o x x x x o x x x x - Count the number of heads in the bottom half (marked with an X below). If the number of heads is odd, the target coin is in the bottom half. Otherwise, it is in the other half.
o o x x x x x x x x