🔧 Step-by-Step Answer Walkthrough For Easy Level
Three cells in the top-right area share a sum-12 constraint. Your highest pip domino is [4–4], and no domino in this set goes above 4. The only way to reach 12 across three cells is if every one of them holds a 4. That's not a guess — it's the only arrangement that works.
Lay [4–4] horizontally across row 0, columns 3 and 4 — both cells show 4. The third cell in the region is row 1, column 3. Stand [4–0] vertically there: 4 at row 1 (completing the sum) and 0 descending to row 2, column 3.
Cells [3,0] and [3,4] are each isolated in their own sum-0 regions, meaning both must be 0. Two of your remaining dominoes carry a 0-end: [1–0] and [0–2]. Place [1–0] horizontally in row 3: the 1 at column 1 and the 0 at column 0 ✓. Place [0–2] horizontally: the 0 at column 4 and the 2 at column 3 ✓.
The equals constraint covers cells [2,1] and [3,1]. You just placed [1–0] so [3,1]=1 — that means [2,1] must also be 1. Only one domino left with a 1-end: [1–3]. Stand it vertically with the 1 at row 2 and the 3 reaching up to row 1. The empty-region cell at [1,1] takes the 3 with no constraint.
The only domino remaining is [2–2], and the only unfilled region is the equals pair at [0,0]–[0,1]. A double-pip domino dropping into an equals region — both cells show 2, constraint satisfied. Puzzle complete.
🔧 Step-by-Step Answer Walkthrough For Medium Level
Row 1 holds a four-cell equals region: every cell must share the same pip value. The [0–0] domino is a natural fit — place it horizontally at [1,2] and [1,3]. With two cells already at 0, the entire equals constraint is committed: all four cells in row 1 must be 0.
Cells [1,0] and [1,1] must also show 0. The [0–4] domino handles [1,0]: orient it vertically with 0 at row 1 and 4 dropping down to [2,0]. The [2–0] domino handles [1,1]: orient it vertically with 0 at row 1 and 2 dropping to [2,1]. Both row-1 cells confirm as 0 ✓.
Cell [2,1] just received a 2 from [2–0]. The less-than region says [2,1] < 3 — 2 satisfies that with room to spare. Now look at the sum-5 pair [2,0]+[3,0]: [2,0]=4 from [0–4], so [3,0] must be 1.
You need a 1 at [3,0] and some value at [4,0]. The [2–1] domino covers both vertically: 2 at [4,0] and 1 at [3,0] — which confirms the sum-5 pair (4+1=5 ✓). The greater-than constraint at [4,0] requires a value above 1, and 2 clears that easily.
The greater-than region at [0,1] and [0,2] demands both cells exceed 0. The [4–4] double domino is the cleanest fit: 4 > 0 at both positions. Drop it horizontally across those two cells.
The pair at [2,2]+[3,2] must sum to 1. The [0–1] domino handles it exactly: place it with 1 at [2,2] and 0 at [3,2]. One cell gets 1, the other gets 0, and 1+0=1 ✓.
One domino and one region remain. The sum-4 pair at [2,3]+[3,3] takes [2–2]: both cells show 2, and 2+2=4 ✓. Every constraint confirmed — puzzle complete.
🔧 Step-by-Step Answer Walkthrough For Hard Level
Cells [4,0], [4,1], [4,5], and [4,6] each sit in their own sum-5 region — single-cell constraints, so all four must be exactly 5. Cell [4,4] is an empty region with no restriction. Start by reading this row before placing anything.
Both [4,0] and [4,1] must be 5 — only the [5–5] double domino can cover them simultaneously. Lay it horizontally there. For [4,5]=5 with [4,4] unconstrained, the [5–0] domino fits: 5 at [4,5] and 0 at [4,4].
Cell [4,6] must be 5. The [1–5] domino runs horizontally: 1 at [4,7] and 5 at [4,6]. The equals pair [4,7]+[4,8] forces [4,8]=1. The [1–4] domino runs vertically here: 1 at [4,8] and 4 at [3,8]. That feeds into the sum-5 pair [2,8]+[3,8]: with [3,8]=4, cell [2,8] must be 1.
Cell [2,8]=1 comes from the [1–6] domino placed vertically: 1 at [2,8] and 6 at [1,8]. The isolated constraint at [1,8] says the value must exceed 5 — 6 is the only pip count that qualifies, and it drops in perfectly.
Single-cell [3,4] must be 5. The [5–2] domino runs vertically: 5 at [3,4] and 2 at [2,4]. That starts the sum-5 triple [2,4]+[2,5]+[2,6]: [2,4]=2, so [2,5]+[2,6]=3. The [2–1] domino fills those cells horizontally: 2 at [2,5] and 1 at [2,6] (2+1=3 ✓).
Cell [2,1] carries a greater-than >5 constraint — it must be 6. The [6–3] domino runs horizontally: 6 at [2,1] and 3 at [2,2] ✓. The sum-5 triple [2,2]+[3,2]+[4,2] now has [2,2]=3, so [3,2]+[4,2]=2. The [1–1] domino runs vertically: 1 at each cell (3+1+1=5 ✓).
Sum-5 pair [0,0]+[0,1]: the [3–2] domino runs horizontally, 3+2=5 ✓. Sum-5 triple [0,4]+[0,5]+[0,6]: the [3–1] domino covers the first two cells (3+1=4), and [0,6] must be 1. The [0–1] domino runs vertically at column 6: 0 at [1,6] (an empty-region cell, no constraint) and 1 at [0,6] — completing 3+1+1=5 ✓. The final domino [0–0] fills the two empty-region cells at [0,2] and [1,2]. Every constraint satisfied — puzzle complete.
💬 Community Discussion
Leave your comment