Add solution and test-cases for problem 2566

leetcode/2501-2600/2566.Maximum-Difference-by-Remapping-a-Digit/README.md

@@ -0,0 +1,42 @@
+# [2566.Maximum Difference by Remapping a Digit][title]
+
+## Description
+
+You are given an integer `num`. You know that Bob will sneakily **remap** one of the `10` possible digits (`0` to `9`) to another digit.
+
+Return the difference between the maximum and minimum values Bob can make by remapping **exactly one** digit in `num`.
+
+**Notes**:
+
+- When Bob remaps a digit d1 to another digit d2, Bob replaces all occurrences of `d1` in `num` with `d2`.
+- Bob can remap a digit to itself, in which case `num` does not change.
+- Bob can remap different digits for obtaining minimum and maximum values respectively.
+- The resulting number after remapping can contain leading zeroes.
+
+**Example 1:**
+
+```
+Input: num = 11891
+Output: 99009
+Explanation: 
+To achieve the maximum value, Bob can remap the digit 1 to the digit 9 to yield 99899.
+To achieve the minimum value, Bob can remap the digit 1 to the digit 0, yielding 890.
+The difference between these two numbers is 99009.
+```
+
+**Example 2:**
+
+```
+Input: num = 90
+Output: 99
+Explanation:
+The maximum value that can be returned by the function is 99 (if 0 is replaced by 9) and the minimum value that can be returned by the function is 0 (if 9 is replaced by 0).
+Thus, we return 99.
+```
+
+## 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/maximum-difference-by-remapping-a-digit
+[me]: https://github.com/kylesliu/awesome-golang-algorithm

leetcode/2501-2600/2566.Maximum-Difference-by-Remapping-a-Digit/Solution.go

@@ -1,5 +1,38 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+func Solution(num int) int {
+	digits := make([]int, 0)
+	for num > 0 {
+		digits = append(digits, num%10)
+		num /= 10
+	}
+	cp1 := make([]int, len(digits))
+	copy(cp1, digits)
+	i := len(digits) - 1
+	remap := -1
+	for ; i >= 0; i-- {
+		if cp1[i] != 9 {
+			remap = cp1[i]
+			break
+		}
+	}
+	for ; i >= 0; i-- {
+		if cp1[i] == remap {
+			cp1[i] = 9
+		}
+	}
+
+	i = len(digits) - 1
+	remap = digits[i]
+	for ; i >= 0; i-- {
+		if digits[i] == remap {
+			digits[i] = 0
+		}
+	}
+	a, b := 0, 0
+	for i := len(digits) - 1; i >= 0; i-- {
+		a = a*10 + cp1[i]
+		b = b*10 + digits[i]
+	}
+	return a - b
 }

leetcode/2501-2600/2566.Maximum-Difference-by-Remapping-a-Digit/Solution_test.go

@@ -10,12 +10,11 @@ func TestSolution(t *testing.T) {
 	//	测试用例
 	cases := []struct {
 		name   string
-		inputs bool
-		expect bool
+		inputs int
+		expect int
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase1", 11891, 99009},
+		{"TestCase2", 90, 99},
 	}
 
 	//	开始测试
@@ -30,10 +29,10 @@ func TestSolution(t *testing.T) {
 	}
 }
 
-//	压力测试
+// 压力测试
 func BenchmarkSolution(b *testing.B) {
 }
 
-//	使用案列
+// 使用案列
 func ExampleSolution() {
 }