update

hard/632.smallest-range.go

@@ -4,24 +4,50 @@ func (a array) Len() int           { return len(a) }
 func (a array) Less(i, j int) bool { return a[i][0] < a[j][0] }
 func (a array) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
 
-type none struct{}
-
 func smallestRange(nums [][]int) []int {
 	var a array
-	set := make(map[int]none)
+	m := make(map[int]int)
 	for i := range nums {
-		for _, num := range nums[i] {
-			a = append(a, []int{num, i})
+		for j := range nums[i] {
+			if num := nums[i][j]; j == 0 || num != nums[i][j-1] {
+				a = append(a, []int{num, i})
+			}
 		}
 	}
 	sort.Sort(a)
-	l, r, k, n := 0, -1, len(nums), len(a)
+	l, r, k, n := 0, 0, len(nums), len(a)
 	min := math.MaxInt32
 	res := make([]int, 2)
 	for r < n {
-		for len(set) != k {
-			r++
-			
+		for r < n && len(m) != k {
+			for {
+				m[a[r][1]]++
+				r++
+				if n-1 < r || a[r-1][0] != a[r][0] {
+					break
+				}
+			}
+		}
+		if len(m) == k && a[r-1][0]-a[l][0] < min {
+			res[0], res[1] = a[l][0], a[r-1][0]
+			min = a[r-1][0] - a[l][0]
+		}
+		for l < r && len(m) == k {
+			for {
+				m[a[l][1]]--
+				if m[a[l][1]] == 0 {
+					delete(m, a[l][1])
+				}
+				l++
+				if len(m) == k && a[r-1][0]-a[l][0] < min {
+					res[0], res[1] = a[l][0], a[r-1][0]
+					min = a[r-1][0] - a[l][0]
+				}
+				if l == r || a[l-1][0] != a[l][0] {
+					break
+				}
+			}
 		}
 	}
+	return res
 }