1089 done

Author: aQuaYi

Algorithms/1089.duplicate-zeros/duplicate-zeros.go

@@ -3,25 +3,27 @@ package problem1089
 func duplicateZeros(A []int) {
 	n := len(A)
 	//
-	i, count := 0, 0
-	for i+count < n {
+	count := 0
+	for i := 0; i < n; i++ {
 		if A[i] == 0 {
 			count++
 		}
-		i++
 	}
-	i--
+	// copy A[i] to A[j]
+	copy := func(i, j int) {
+		if j < n {
+			A[j] = A[i]
+		}
+	}
 	//
-	j := n - 1
-	for count > 0 {
+	i, j := n-1, n+count-1
+	for i < j {
+		copy(i, j)
 		if A[i] == 0 {
-			A[j-1], A[j] = 0, 0
-			j -= 2
-			count--
-		} else {
-			A[j] = A[i]
 			j--
+			copy(i, j)
 		}
 		i--
+		j--
 	}
 }

Algorithms/1089.duplicate-zeros/duplicate-zeros_test.go

@@ -12,6 +12,17 @@ var tcs = []struct {
 	ans []int
 }{
 
+	{
+
+		[]int{8, 4, 5, 0, 0, 0, 0, 7},
+		[]int{8, 4, 5, 0, 0, 0, 0, 0},
+	},
+
+	{
+		[]int{0, 0, 0, 0, 0, 0, 0, 0},
+		[]int{0, 0, 0, 0, 0, 0, 0, 0},
+	},
+
 	{
 		[]int{0, 0, 0, 0, 0, 0, 0},
 		[]int{0, 0, 0, 0, 0, 0, 0},