diff --git a/leetcode/2501-2600/2598.Smallest-Missing-Non-negative-Integer-After-Operations/README.md b/leetcode/2501-2600/2598.Smallest-Missing-Non-negative-Integer-After-Operations/README.md
new file mode 100644
index 000000000..cbde628d8
--- /dev/null
+++ b/leetcode/2501-2600/2598.Smallest-Missing-Non-negative-Integer-After-Operations/README.md
@@ -0,0 +1,43 @@
+# [2598.Smallest Missing Non-negative Integer After Operations][title]
+
+## Description
+You are given a **0-indexed** integer array `nums` and an integer `value`.
+
+In one operation, you can add or subtract `value` from any element of `nums`.
+
+- For example, if `nums = [1,2,3]` and `value = 2`, you can choose to subtract `value` from `nums[0]` to make `nums = [-1,2,3]`.
+
+The MEX (minimum excluded) of an array is the smallest missing **non-negative** integer in it.
+
+- For example, the MEX of `[-1,2,3]` is `0` while the MEX of `[1,0,3]` is `2`.
+
+Return the maximum MEX of `nums` after applying the mentioned operation **any number of times**.
+
+**Example 1:**
+
+```
+Input: nums = [1,-10,7,13,6,8], value = 5
+Output: 4
+Explanation: One can achieve this result by applying the following operations:
+- Add value to nums[1] twice to make nums = [1,0,7,13,6,8]
+- Subtract value from nums[2] once to make nums = [1,0,2,13,6,8]
+- Subtract value from nums[3] twice to make nums = [1,0,2,3,6,8]
+The MEX of nums is 4. It can be shown that 4 is the maximum MEX we can achieve.
+```
+
+**Example 2:**
+
+```
+Input: nums = [1,-10,7,13,6,8], value = 7
+Output: 2
+Explanation: One can achieve this result by applying the following operation:
+- subtract value from nums[2] once to make nums = [1,-10,0,13,6,8]
+The MEX of nums is 2. It can be shown that 2 is the maximum MEX we can achieve.
+```
+
+## 结语
+
+如果你同我一样热爱数据结构、算法、LeetCode，可以关注我 GitHub 上的 LeetCode 题解：[awesome-golang-algorithm][me]
+
+[title]: https://leetcode.com/problems/smallest-missing-non-negative-integer-after-operations
+[me]: https://github.com/kylesliu/awesome-golang-algorithm
diff --git a/leetcode/2501-2600/2598.Smallest-Missing-Non-negative-Integer-After-Operations/Solution.go b/leetcode/2501-2600/2598.Smallest-Missing-Non-negative-Integer-After-Operations/Solution.go
index d115ccf5e..01937e8f0 100755
--- a/leetcode/2501-2600/2598.Smallest-Missing-Non-negative-Integer-After-Operations/Solution.go
+++ b/leetcode/2501-2600/2598.Smallest-Missing-Non-negative-Integer-After-Operations/Solution.go
@@ -1,5 +1,15 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+func Solution(nums []int, value int) int {
+	mp := make([]int, value)
+	for _, x := range nums {
+		v := ((x % value) + value) % value
+		mp[v]++
+	}
+	mex := 0
+	for mp[mex%value] > 0 {
+		mp[mex%value]--
+		mex++
+	}
+	return mex
 }
diff --git a/leetcode/2501-2600/2598.Smallest-Missing-Non-negative-Integer-After-Operations/Solution_test.go b/leetcode/2501-2600/2598.Smallest-Missing-Non-negative-Integer-After-Operations/Solution_test.go
index 14ff50eb4..e572841ed 100755
--- a/leetcode/2501-2600/2598.Smallest-Missing-Non-negative-Integer-After-Operations/Solution_test.go
+++ b/leetcode/2501-2600/2598.Smallest-Missing-Non-negative-Integer-After-Operations/Solution_test.go
@@ -10,30 +10,30 @@ func TestSolution(t *testing.T) {
 	//	测试用例
 	cases := []struct {
 		name   string
-		inputs bool
-		expect bool
+		inputs []int
+		value  int
+		expect int
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase1", []int{1, -10, 7, 13, 6, 8}, 5, 4},
+		{"TestCase2", []int{1, -10, 7, 13, 6, 8}, 7, 2},
 	}
 
 	//	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.inputs, c.value)
 			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",
+					c.expect, got, c.inputs, c.value)
 			}
 		})
 	}
 }
 
-//	压力测试
+// 压力测试
 func BenchmarkSolution(b *testing.B) {
 }
 
-//	使用案列
+// 使用案列
 func ExampleSolution() {
 }