添加 18 题

leetcode/0171.Excel-Sheet-Column-Number/171. Excel Sheet Column Number.go

@@ -0,0 +1,10 @@
+package leetcode
+
+func titleToNumber(s string) int {
+	val, res := 0, 0
+	for i := 0; i < len(s); i++ {
+		val = int(s[i] - 'A' + 1)
+		res = res*26 + val
+	}
+	return res
+}

leetcode/0171.Excel-Sheet-Column-Number/171. Excel Sheet Column Number_test.go

@@ -0,0 +1,57 @@
+package leetcode
+
+import (
+	"fmt"
+	"testing"
+)
+
+type question171 struct {
+	para171
+	ans171
+}
+
+// para 是参数
+// one 代表第一个参数
+type para171 struct {
+	s string
+}
+
+// ans 是答案
+// one 代表第一个答案
+type ans171 struct {
+	one int
+}
+
+func Test_Problem171(t *testing.T) {
+
+	qs := []question171{
+
+		question171{
+			para171{"A"},
+			ans171{1},
+		},
+
+		question171{
+			para171{"AB"},
+			ans171{28},
+		},
+
+		question171{
+			para171{"ZY"},
+			ans171{701},
+		},
+
+		question171{
+			para171{"ABC"},
+			ans171{731},
+		},
+	}
+
+	fmt.Printf("------------------------Leetcode Problem 171------------------------\n")
+
+	for _, q := range qs {
+		_, p := q.ans171, q.para171
+		fmt.Printf("【input】:%v       【output】:%v\n", p, titleToNumber(p.s))
+	}
+	fmt.Printf("\n\n\n")
+}

leetcode/0171.Excel-Sheet-Column-Number/README.md

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+# [171. Excel Sheet Column Number](https://leetcode.com/problems/excel-sheet-column-number/)
+
+
+## 题目
+
+Given a column title as appear in an Excel sheet, return its corresponding column number.
+
+For example:
+
+```
+    A -> 1
+    B -> 2
+    C -> 3
+    ...
+    Z -> 26
+    AA -> 27
+    AB -> 28 
+    ...
+```
+
+**Example 1**:
+
+```
+Input: "A"
+Output: 1
+```
+
+**Example 2**:
+
+```
+Input: "AB"
+Output: 28
+```
+
+**Example 3**:
+
+```
+Input: "ZY"
+Output: 701
+```
+
+## 题目大意
+
+给定一个 Excel 表格中的列名称，返回其相应的列序号。
+
+
+## 解题思路
+
+- 给出 Excel 中列的名称，输出其对应的列序号。
+- 简单题。这一题是第 168 题的逆序题。按照 26 进制还原成十进制即可。
+
+## 代码
+
+```go
+
+package leetcode
+
+func titleToNumber(s string) int {
+	val, res := 0, 0
+	for i := 0; i < len(s); i++ {
+		val = int(s[i] - 'A' + 1)
+		res = res*26 + val
+	}
+	return res
+}
+
+```