diff --git a/Algorithms/0721. Accounts Merge/721. Accounts Merge.go b/Algorithms/0721. Accounts Merge/721. Accounts Merge.go
new file mode 100644
index 00000000..82f0789e
--- /dev/null
+++ b/Algorithms/0721. Accounts Merge/721. Accounts Merge.go	
@@ -0,0 +1,88 @@
+package leetcode
+
+import "sort"
+
+// 解法一 并查集优化搜索解法
+func accountsMerge(accounts [][]string) (r [][]string) {
+	uf := UnionFind{}
+	uf.init(len(accounts))
+	// emailToID 将所有的 email 邮箱都拆开，拆开与 id(数组下标) 对应
+	// idToName 将 id(数组下标) 与 name 对应
+	// idToEmails 将 id(数组下标) 与整理好去重以后的 email 组对应
+	emailToID, idToName, idToEmails, res := make(map[string]int), make(map[int]string), make(map[int][]string), [][]string{}
+	for id, acc := range accounts {
+		idToName[id] = acc[0]
+		for i := 1; i < len(acc); i++ {
+			pid, ok := emailToID[acc[i]]
+			if ok {
+				uf.union(id, pid)
+			}
+			emailToID[acc[i]] = id
+		}
+	}
+	for email, id := range emailToID {
+		pid := uf.find(id)
+		idToEmails[pid] = append(idToEmails[pid], email)
+	}
+	for id, emails := range idToEmails {
+		name := idToName[id]
+		sort.Strings(emails)
+		res = append(res, append([]string{name}, emails...))
+	}
+	return res
+}
+
+// 解法二 并查集暴力解法
+func accountsMerge1(accounts [][]string) [][]string {
+	if len(accounts) == 0 {
+		return [][]string{}
+	}
+	uf, res, visited := UnionFind{}, [][]string{}, map[int]bool{}
+	uf.init(len(accounts))
+	for i := 0; i < len(accounts); i++ {
+		for j := i + 1; j < len(accounts); j++ {
+			if accounts[i][0] == accounts[j][0] {
+				tmpA, tmpB, flag := accounts[i][1:], accounts[j][1:], false
+				for j := 0; j < len(tmpA); j++ {
+					for k := 0; k < len(tmpB); k++ {
+						if tmpA[j] == tmpB[k] {
+							flag = true
+							break
+						}
+					}
+					if flag {
+						break
+					}
+				}
+				if flag {
+					uf.union(i, j)
+				}
+			}
+		}
+	}
+	for i := 0; i < len(accounts); i++ {
+		if visited[i] {
+			continue
+		}
+		emails, account, tmpMap := accounts[i][1:], []string{accounts[i][0]}, map[string]string{}
+		for j := i + 1; j < len(accounts); j++ {
+			if uf.find(j) == uf.find(i) {
+				visited[j] = true
+				for _, v := range accounts[j][1:] {
+					tmpMap[v] = v
+				}
+			}
+		}
+		for _, v := range emails {
+			tmpMap[v] = v
+		}
+		emails = []string{}
+		for key := range tmpMap {
+			emails = append(emails, key)
+		}
+		sort.Strings(emails)
+		account = append(account, emails...)
+		res = append(res, account)
+	}
+	return res
+}
diff --git a/Algorithms/0721. Accounts Merge/721. Accounts Merge_test.go b/Algorithms/0721. Accounts Merge/721. Accounts Merge_test.go
new file mode 100644
index 00000000..d0dd8bcd
--- /dev/null
+++ b/Algorithms/0721. Accounts Merge/721. Accounts Merge_test.go	
@@ -0,0 +1,73 @@
+package leetcode
+
+import (
+	"fmt"
+	"testing"
+)
+
+type question721 struct {
+	para721
+	ans721
+}
+
+// para 是参数
+// one 代表第一个参数
+type para721 struct {
+	w [][]string
+}
+
+// ans 是答案
+// one 代表第一个答案
+type ans721 struct {
+	one [][]string
+}
+
+func Test_Problem721(t *testing.T) {
+
+	qs := []question721{
+
+		question721{
+			para721{[][]string{[]string{"John", "johnsmith@mail.com", "john00@mail.com"},
+				[]string{"John", "johnnybravo@mail.com"},
+				[]string{"John", "johnsmith@mail.com", "john_newyork@mail.com"},
+				[]string{"Mary", "mary@mail.com"}}},
+			ans721{[][]string{[]string{"John", "john00@mail.com", "john_newyork@mail.com", "johnsmith@mail.com"},
+				[]string{"John", "johnnybravo@mail.com"},
+				[]string{"Mary", "mary@mail.com"}}},
+		},
+
+		question721{
+			para721{[][]string{[]string{"Alex", "Alex5@m.co", "Alex4@m.co", "Alex0@m.co"},
+				[]string{"Ethan", "Ethan3@m.co", "Ethan3@m.co", "Ethan0@m.co"},
+				[]string{"Kevin", "Kevin4@m.co", "Kevin2@m.co", "Kevin2@m.co"},
+				[]string{"Gabe", "Gabe0@m.co", "Gabe3@m.co", "Gabe2@m.co"},
+				[]string{"Gabe", "Gabe3@m.co", "Gabe4@m.co", "Gabe2@m.co"}}},
+			ans721{[][]string{[]string{"Alex", "Alex0@m.co", "Alex4@m.co", "Alex5@m.co"},
+				[]string{"Ethan", "Ethan0@m.co", "Ethan3@m.co"},
+				[]string{"Gabe", "Gabe0@m.co", "Gabe2@m.co", "Gabe3@m.co", "Gabe4@m.co"},
+				[]string{"Kevin", "Kevin2@m.co", "Kevin4@m.co"}}},
+		},
+
+		question721{
+			para721{[][]string{[]string{"David", "David0@m.co", "David4@m.co", "David3@m.co"},
+				[]string{"David", "David5@m.co", "David5@m.co", "David0@m.co"},
+				[]string{"David", "David1@m.co", "David4@m.co", "David0@m.co"},
+				[]string{"David", "David0@m.co", "David1@m.co", "David3@m.co"},
+				[]string{"David", "David4@m.co", "David1@m.co", "David3@m.co"}}},
+			ans721{[][]string{[]string{"David", "David0@m.co", "David1@m.co", "David3@m.co", "David4@m.co", "David5@m.co"}}},
+		},
+
+		question721{
+			para721{[][]string{}},
+			ans721{[][]string{}},
+		},
+	}
+
+	fmt.Printf("------------------------Leetcode Problem 721------------------------\n")
+
+	for _, q := range qs {
+		_, p := q.ans721, q.para721
+		fmt.Printf("【input】:%v       【output】:%v\n", p, accountsMerge(p.w))
+	}
+	fmt.Printf("\n\n\n")
+}