228 UT pass

Author: aQua

Algorithms/0228.summary-ranges/README.md

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+# [228. Summary Ranges](https://leetcode.com/problems/summary-ranges/)
+
+## 题目
+Given a sorted integer array without duplicates, return the summary of its ranges.
+
+Example 1:
+```
+Input: [0,1,2,4,5,7]
+Output: ["0->2","4->5","7"]
+```
+
+Example 2:
+```
+Input: [0,2,3,4,6,8,9]
+Output: ["0","2->4","6","8->9"]
+```
+
+
+## 解题思路
+
+见程序注释

Algorithms/0228.summary-ranges/summary-ranges.go

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+package Problem0228
+
+import (
+	"fmt"
+)
+
+func summaryRanges(a []int) []string {
+	res := []string{}
+
+	l := len(a)
+	if l == 0 {
+		return res
+	}
+
+	begin := a[0]
+	str := ""
+	for i := 1; i < l; i++ {
+		if a[i-1]+1 != a[i] {
+			if a[i-1] == begin {
+				str = fmt.Sprintf("%d", begin)
+			} else {
+				str = fmt.Sprintf("%d->%d", begin, a[i-1])
+			}
+			begin = a[i]
+			res = append(res, str)
+		}
+	}
+	if a[l-1] == begin {
+		str = fmt.Sprintf("%d", begin)
+	} else {
+		str = fmt.Sprintf("%d->%d", begin, a[l-1])
+	}
+	res = append(res, str)
+
+	return res
+}

Algorithms/0228.summary-ranges/summary-ranges_test.go

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+package Problem0228
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+type question struct {
+	para
+	ans
+}
+
+// para 是参数
+type para struct {
+	nums []int
+}
+
+// ans 是答案
+type ans struct {
+	one []string
+}
+
+func Test_Problem0228(t *testing.T) {
+	ast := assert.New(t)
+
+	qs := []question{
+
+		question{
+			para{
+				[]int{0, 1, 2, 4, 5, 7},
+			},
+			ans{
+				[]string{"0->2", "4->5", "7"},
+			},
+		},
+
+		question{
+			para{
+				[]int{0, 2, 3, 4, 6, 8, 9},
+			},
+			ans{
+				[]string{"0", "2->4", "6", "8->9"},
+			},
+		},
+		// 如需多个测试，可以复制上方元素。
+	}
+
+	for _, q := range qs {
+		a, p := q.ans, q.para
+		fmt.Printf("~~%v~~\n", p)
+
+		ast.Equal(a.one, summaryRanges(p.nums), "输入:%v", p)
+	}
+}