Merge pull request #1406 from 0xff-dev/960

Add solution and test-cases for problem 960

Author: 6boris

leetcode/901-1000/0960.Delete-Columns-to-Make-Sorted-III/README.md

@@ -1,28 +1,39 @@
 # [960.Delete Columns to Make Sorted III][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
+You are given an array of `n` strings `strs`, all of the same length.
+
+We may choose any deletion indices, and we delete all the characters in those indices for each string.
+
+For example, if we have `strs = ["abcdef","uvwxyz"]` and deletion indices `{0, 2, 3}`, then the final array after deletions is `["bef", "vyz"]`.
+
+Suppose we chose a set of deletion indices answer such that after deletions, the final array has **every string (row) in lexicographic** order. (i.e., `(strs[0][0] <= strs[0][1] <= ... <= strs[0][strs[0].length - 1])`, and `(strs[1][0] <= strs[1][1] <= ... <= strs[1][strs[1].length - 1])`, and so on). Return the minimum possible value of `answer.length`.
 
 **Example 1:**
 
 ```
-Input: a = "11", b = "1"
-Output: "100"
+Input: strs = ["babca","bbazb"]
+Output: 3
+Explanation: After deleting columns 0, 1, and 4, the final array is strs = ["bc", "az"].
+Both these rows are individually in lexicographic order (ie. strs[0][0] <= strs[0][1] and strs[1][0] <= strs[1][1]).
+Note that strs[0] > strs[1] - the array strs is not necessarily in lexicographic order.
 ```
 
-## 题意
-> ...
-
-## 题解
+**Example 2:**
 
-### 思路1
-> ...
-Delete Columns to Make Sorted III
-```go
 ```
+Input: strs = ["edcba"]
+Output: 4
+Explanation: If we delete less than 4 columns, the only row will not be lexicographically sorted.
+```
+
+**Example 3:**
 
+```
+Input: strs = ["ghi","def","abc"]
+Output: 0
+Explanation: All rows are already lexicographically sorted.
+```
 
 ## 结语
 

leetcode/901-1000/0960.Delete-Columns-to-Make-Sorted-III/Solution.go

@@ -1,5 +1,41 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+func Solution(A []string) int {
+	if len(A) == 0 {
+		return 0
+	}
+
+	numCols := len(A[0])
+	dp := make([]int, numCols)
+
+	for i := range dp {
+		dp[i] = 1
+	}
+
+	for i := numCols - 2; i >= 0; i-- {
+		for j := i + 1; j < numCols; j++ {
+			isSorted := true
+			for _, row := range A {
+				if row[i] > row[j] {
+					isSorted = false
+					break
+				}
+			}
+
+			if isSorted {
+				if dp[j]+1 > dp[i] {
+					dp[i] = dp[j] + 1
+				}
+			}
+		}
+	}
+
+	maxKept := 0
+	for _, val := range dp {
+		if val > maxKept {
+			maxKept = val
+		}
+	}
+
+	return numCols - maxKept
 }

leetcode/901-1000/0960.Delete-Columns-to-Make-Sorted-III/Solution_test.go

@@ -10,12 +10,12 @@ func TestSolution(t *testing.T) {
 	//	测试用例
 	cases := []struct {
 		name   string
-		inputs bool
-		expect bool
+		inputs []string
+		expect int
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase1", []string{"babca", "bbazb"}, 3},
+		{"TestCase2", []string{"edcba"}, 4},
+		{"TestCase3", []string{"ghi", "def", "abc"}, 0},
 	}
 
 	//	开始测试
@@ -30,10 +30,10 @@ 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() {
 }