Merge pull request #600 from 0xff-dev/1203

Add solution and test-cases for problem 1203

leetcode/1201-1300/1203.Sort-Items-by-Groups-Respecting-Dependencies/README.md

@@ -1,28 +1,31 @@
 # [1203.Sort Items by Groups Respecting Dependencies][title]
 
-> [!WARNING|style:flat]
-> This question is temporarily unanswered if you have good ideas. Welcome to [Create Pull Request PR](https://github.com/kylesliu/awesome-golang-algorithm)
-
 ## Description
+There are `n` items each belonging to zero or one of `m` groups where `group[i]` is the group that the `i`-th item belongs to and it's equal to `-1` if the `i`-th item belongs to no group. The items and the groups are zero indexed. A group can have no item belonging to it.
 
-**Example 1:**
+Return a sorted list of the items such that:
 
-```
-Input: a = "11", b = "1"
-Output: "100"
-```
+- The items that belong to the same group are next to each other in the sorted list.
+- There are some relations between these items where `beforeItems[i]` is a list containing all the items that should come before the `i`-th item in the sorted array (to the left of the `i`-th item).
+
+Return any solution if there is more than one solution and return an **empty list** if there is no solution.
 
-## 题意
-> ...
+**Example 1:**  
 
-## 题解
+![example1](./1359_ex1.png)
 
-### 思路1
-> ...
-Sort Items by Groups Respecting Dependencies
-```go
 ```
+Input: n = 8, m = 2, group = [-1,-1,1,0,0,1,0,-1], beforeItems = [[],[6],[5],[6],[3,6],[],[],[]]
+Output: [6,3,4,1,5,2,0,7]
+```
+
+**Example 2:**
 
+```
+Input: n = 8, m = 2, group = [-1,-1,1,0,0,1,0,-1], beforeItems = [[],[6],[5],[6],[3],[],[4],[]]
+Output: []
+Explanation: This is the same as example 1 except that 4 needs to be before 6 in the sorted list.
+```
 
 ## 结语
 

leetcode/1201-1300/1203.Sort-Items-by-Groups-Respecting-Dependencies/Solution.go

@@ -1,5 +1,163 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+import "sort"
+
+func Solution(n int, m int, group []int, beforeItems [][]int) []int {
+	groupItems := make(map[int][]int)
+	item2Group := make(map[int]int)
+	for idx, g := range group {
+		if g == -1 {
+			g = m + idx
+		}
+		item2Group[idx] = g
+		if _, ok := groupItems[g]; !ok {
+			groupItems[g] = make([]int, 0)
+		}
+		groupItems[g] = append(groupItems[g], idx)
+	}
+
+	/*
+		for g, items := range groupItems {
+			fmt.Printf("group: %d -- %v\n", g, items)
+		}
+		for item, g := range item2Group {
+			fmt.Printf("itme: %d -- %d\n", item, g)
+		}
+	*/
+	groupItemOrder := make(map[int]map[int][]int)
+	groupItemIn := make(map[int]map[int]int)
+
+	groupOrder := make(map[int][]int)
+	groupIn := make(map[int]int)
+	for idx, before := range beforeItems {
+		idxGroup := item2Group[idx]
+
+		for _, item := range before {
+			itemGroup := item2Group[item]
+			if itemGroup == idxGroup {
+				if _, ok := groupItemOrder[idxGroup]; !ok {
+					groupItemOrder[idxGroup] = make(map[int][]int)
+				}
+				if _, ok := groupItemOrder[idxGroup][item]; !ok {
+					groupItemOrder[idxGroup][item] = make([]int, 0)
+				}
+				groupItemOrder[idxGroup][item] = append(groupItemOrder[idxGroup][item], idx)
+
+				if _, ok := groupItemIn[idxGroup]; !ok {
+					groupItemIn[idxGroup] = make(map[int]int)
+				}
+				groupItemIn[idxGroup][idx]++
+				continue
+			}
+			if _, ok := groupOrder[itemGroup]; !ok {
+				groupOrder[itemGroup] = make([]int, 0)
+			}
+			groupOrder[itemGroup] = append(groupOrder[itemGroup], idxGroup)
+			groupIn[idxGroup]++
+		}
+	}
+
+	/*
+		fmt.Printf("groupItemOrder; %+v\n", groupItemOrder)
+		fmt.Printf("groupOrder: %+v\n", groupOrder)
+		fmt.Printf("groupIn: %+v\n", groupIn)
+	*/
+	var groupTopology func(int) bool
+	groupTopology = func(groupID int) bool {
+		items := groupItems[groupID]
+		if len(items) == 1 {
+			return true
+		}
+		newOrder := make([]int, 0)
+		relation := groupItemOrder[groupID]
+		in := groupItemIn[groupID]
+
+		queue := make([]int, 0)
+		used := 0
+		for _, item := range items {
+			if _, ok := in[item]; !ok {
+				queue = append(queue, item)
+				newOrder = append(newOrder, item)
+				used++
+			}
+		}
+		if len(queue) == 0 {
+			return false
+		}
+		// The sorting is added here for test cases, and can be removed from the actual commit code
+		sort.Ints(newOrder)
+		for len(queue) > 0 {
+			n := make([]int, 0)
+			for _, i := range queue {
+				for _, rel := range relation[i] {
+					in[rel]--
+					if in[rel] == 0 {
+						n = append(n, rel)
+					}
+				}
+			}
+			if len(n) == 0 && used != len(items) {
+				return false
+			}
+			queue = n
+			used += len(n)
+			// The sorting is added here for test cases, and can be removed from the actual commit code
+			sort.Ints(n)
+			newOrder = append(newOrder, n...)
+		}
+
+		groupItems[groupID] = newOrder
+		return true
+	}
+	// 先检查每个组是否可以满足要求
+	for groupID := range groupItems {
+		if !groupTopology(groupID) {
+			//fmt.Printf("group; %d, don't", groupID)
+			return nil
+		}
+	}
+
+	queue := make([]int, 0)
+	newGroupOrder := make([]int, 0)
+	used := 0
+	for i := range groupItems {
+		if _, ok := groupIn[i]; !ok {
+			queue = append(queue, i)
+			//fmt.Printf("add group: %d\n", i)
+			newGroupOrder = append(newGroupOrder, i)
+			used++
+		}
+	}
+	if used == 0 {
+		return nil
+	}
+	// The sorting is added here for test cases, and can be removed from the actual commit code
+	sort.Ints(newGroupOrder)
+
+	for len(queue) > 0 {
+		n := make([]int, 0)
+		for _, item := range queue {
+			for _, rel := range groupOrder[item] {
+				groupIn[rel]--
+				if groupIn[rel] == 0 {
+					n = append(n, rel)
+				}
+			}
+		}
+		if len(n) == 0 && used != len(groupItems) {
+			return nil
+		}
+		queue = n
+		// The sorting is added here for test cases, and can be removed from the actual commit code
+		sort.Ints(n)
+		newGroupOrder = append(newGroupOrder, n...)
+		used += len(n)
+	}
+
+	ans := make([]int, 0)
+	for _, g := range newGroupOrder {
+		ans = append(ans, groupItems[g]...)
+	}
+
+	return ans
 }

leetcode/1201-1300/1203.Sort-Items-by-Groups-Respecting-Dependencies/Solution_test.go

@@ -9,31 +9,36 @@ import (
 func TestSolution(t *testing.T) {
 	//	测试用例
 	cases := []struct {
-		name   string
-		inputs bool
-		expect bool
+		name        string
+		n, m        int
+		group       []int
+		beforeItems [][]int
+		expect      []int
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase1", 8, 2, []int{-1, -1, 1, 0, 0, 1, 0, -1}, [][]int{
+			{}, {6}, {5}, {6}, {3, 6}, {}, {}, {},
+		}, []int{6, 3, 4, 5, 2, 0, 7, 1}},
+		{"TestCase2", 8, 2, []int{-1, -1, 1, 0, 0, 1, 0, -1}, [][]int{
+			{}, {6}, {5}, {6}, {3}, {}, {4}, {},
+		}, nil},
 	}
 
 	//	开始测试
 	for i, c := range cases {
 		t.Run(c.name+" "+strconv.Itoa(i), func(t *testing.T) {
-			got := Solution(c.inputs)
+			got := Solution(c.n, c.m, c.group, c.beforeItems)
 			if !reflect.DeepEqual(got, c.expect) {
-				t.Fatalf("expected: %v, but got: %v, with inputs: %v",
-					c.expect, got, c.inputs)
+				t.Fatalf("expected: %v, but got: %v, with inputs: %v %v %v %v",
+					c.expect, got, c.n, c.m, c.group, c.beforeItems)
 			}
 		})
 	}
 }
 
-//	压力测试
+// 压力测试
 func BenchmarkSolution(b *testing.B) {
 }
 
-//	使用案列
+// 使用案列
 func ExampleSolution() {
 }