leetcode 1473

leetcode/1473/1473.go

@@ -0,0 +1,64 @@
+func min(a, b int) int {
+    if a < b {
+        return a
+    }
+    return b
+}
+
+type Status [3]int
+var IF = map[bool]int{true: 1, false: 0}
+
+func minCost(houses []int, cost [][]int, m, n, target int) int {
+    const INF = math.MaxInt32
+    mem := make(map[Status]int)
+
+
+    var dfs func (cur, target, color int) int
+    dfs = func(cur, target, color int) (res int) {
+        res = INF
+
+        if r, e := mem[Status{cur, target, color}]; e {
+            return r
+        }
+        defer func () {
+            mem[Status{cur, target, color}] = res
+        } ()
+
+        if target == -1 || cur + target > m {
+            return INF
+        }
+        if cur == m {
+            return 0
+        }
+
+        if houses[cur] != 0 {
+            res = min(
+                res,
+                dfs(
+                    cur + 1, 
+                    target - IF[houses[cur] != color], 
+                    houses[cur],
+                ),
+            )
+        } else {
+            for i := 1; i <= n; i++ {
+                res = min(
+                    res,
+                    dfs(
+                        cur + 1, 
+                        target - IF[i != color], 
+                        i,
+                    ) + cost[cur][i-1],
+                )
+            }
+        }
+        return
+    }
+    
+    ans := dfs(0, target, -1)
+    if ans == INF {
+        ans = -1
+    }
+
+    return ans
+}