Exact Count in Group
The clue states that exactly N cells in a named group — a row, column, edge ring, corner set, neighborhood, or directional slice — have the given status (Suspect or Innocent). The constraint is strict equality: the count must be exactly N, never more, never less. Once you have confirmed enough cells in that group, the rest are forced. Common mistake: treating this as a minimum when you should be eliminating the last unknown cell the moment you reach the stated count.
Reading the examples
“There are exactly N suspects in row 1”
The clue says there is exactly 1 suspect in row 1. The revealed cells already account for all 1, so the remaining cells must be innocent.
“There are exactly N suspects in column A”
The clue says there is exactly 1 suspect in column A. The revealed cells already account for all 1, so the remaining cells must be innocent.
“X has exactly N suspect neighbors”
The clue says there are exactly 2 suspects in Eve's neighbors. The revealed cells already account for all 2, so the remaining cells must be innocent.
“There are exactly N suspects in the edge”
The clue says there are exactly 2 suspects in the edge. The revealed cells already account for all 2, so the remaining cells must be innocent.
“There are exactly N suspects in the corners”
The clue says there is exactly 1 suspect in the corners. The revealed cells already account for all 1, so the remaining cells must be innocent.
“There are exactly N suspects in between Y and Z”
The clue says there is exactly 1 suspect in between Alice and Carol. Among the revealed cells, no suspects already confirmed, and 1 cell remains unknown. So the remaining cell must be suspect to reach exactly 1.
“There are exactly N suspects to the left of Y”
The clue says there are exactly 2 suspects in to the left of Frank. Among the revealed cells, no suspects already confirmed, and 2 cells remain unknown. So both remaining cells must be suspect to reach exactly 2.
“There are exactly N suspects in people with glasses”
The clue says there is exactly 1 suspect in people with glasses. The revealed cells already account for all 1, so the remaining cells must be innocent.