1221 done

Author: aQuaYi

.vscode/settings.json

@@ -32,7 +32,9 @@
         "LLLDDDDD",
         "LLLLD",
         "LLLLDDD",
+        "LLLLRRRR",
         "LLLLUUUU",
+        "LLLRRR",
         "LLLUU",
         "LLUU",
         "Leet",
@@ -42,7 +44,10 @@
         "Paddr",
         "Puerkito",
         "Qedo",
+        "RLLLLRRRLR",
+        "RLRRLLRLRL",
         "RRDD",
+        "RRLL",
         "RRRD",
         "RRRRU",
         "RRRU",
@@ -248,6 +253,7 @@
         "size",
         "sort",
         "split",
+        "splitted",
         "ssaaedd",
         "stretchr",
         "string",

Algorithms/1221.split-a-string-in-balanced-strings/README.md

@@ -0,0 +1,36 @@
+# [1221. Split a String in Balanced Strings](https://leetcode.com/problems/split-a-string-in-balanced-strings/)
+
+Balanced strings are those who have equal quantity of 'L' and 'R' characters.
+
+Given a balanced string s split it in the maximum amount of balanced strings.
+
+Return the maximum amount of splitted balanced strings.
+
+Example 1:
+
+```text
+Input: s = "RLRRLLRLRL"
+Output: 4
+Explanation: s can be split into "RL", "RRLL", "RL", "RL", each substring contains same number of 'L' and 'R'.
+```
+
+Example 2:
+
+```text
+Input: s = "RLLLLRRRLR"
+Output: 3
+Explanation: s can be split into "RL", "LLLRRR", "LR", each substring contains same number of 'L' and 'R'.
+```
+
+Example 3:
+
+```text
+Input: s = "LLLLRRRR"
+Output: 1
+Explanation: s can be split into "LLLLRRRR".
+```
+
+Constraints:
+
+- `1 <= s.length <= 1000`
+- `s[i] = 'L' or 'R'`

Algorithms/1221.split-a-string-in-balanced-strings/split-a-string-in-balanced-strings.go

@@ -0,0 +1,16 @@
+package problem1221
+
+func balancedStringSplit(s string) int {
+	res, count := 0, 0
+	for _, b := range s {
+		if b == 'L' {
+			count++
+		} else {
+			count--
+		}
+		if count == 0 {
+			res++
+		}
+	}
+	return res
+}

Algorithms/1221.split-a-string-in-balanced-strings/split-a-string-in-balanced-strings_test.go

@@ -0,0 +1,47 @@
+package problem1221
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+// tcs is testcase slice
+var tcs = []struct {
+	s   string
+	ans int
+}{
+
+	{
+		"RLRRLLRLRL",
+		4,
+	},
+
+	{
+		"RLLLLRRRLR",
+		3,
+	},
+
+	{
+		"LLLLRRRR",
+		1,
+	},
+
+	// 可以有多个 testcase
+}
+
+func Test_balancedStringSplit(t *testing.T) {
+	a := assert.New(t)
+
+	for _, tc := range tcs {
+		a.Equal(tc.ans, balancedStringSplit(tc.s), "输入:%v", tc)
+	}
+}
+
+func Benchmark_balancedStringSplit(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		for _, tc := range tcs {
+			balancedStringSplit(tc.s)
+		}
+	}
+}