added Problem 14

Author: aQua

Algorithms/0014.longest-common-prefix/README.md

@@ -1,10 +1,10 @@
 # [14. Longest Common Prefix](https://leetcode.com/problems/longest-common-prefix/)
 
 ## 题目
-
+Write a function to find the longest common prefix string amongst an array of strings.
 
 ## 解题思路
-
+1. 
 
 ## 总结
 

Algorithms/0014.longest-common-prefix/longest-common-prefix.go

@@ -1,2 +1,30 @@
 package Problem0014
 
+func longestCommonPrefix(strs []string) string {
+	short := shortest(strs)
+
+	for i, r := range short {
+		for j := 0; j < len(strs); j++ {
+			if strs[j][i] != byte(r) {
+				return strs[j][:i]
+			}
+		}
+	}
+
+	return short
+}
+
+func shortest(strs []string) string {
+	if len(strs) == 0 {
+		return ""
+	}
+
+	res := strs[0]
+	for _, s := range strs {
+		if len(res) > len(s) {
+			res = s
+		}
+	}
+
+	return res
+}

Algorithms/0014.longest-common-prefix/longest-common-prefix_test.go

@@ -14,7 +14,7 @@ type question struct {
 // para 是参数
 // one 代表第一个参数
 type para struct {
-	one string
+	one []string
 }
 
 // ans 是答案
@@ -27,18 +27,30 @@ func Test_Problem0014(t *testing.T) {
 	ast := assert.New(t)
 
 	qs := []question{
-
 		question{
-			para{""},
+			para{
+				[]string{"abcdd", "abcde", "ab"},
+			},
+			ans{"ab"},
+		},
+		question{
+			para{
+				[]string{"abcdd", "abcde"},
+			},
+			ans{"abcd"},
+		},
+		question{
+			para{
+				[]string{},
+			},
 			ans{""},
 		},
-	
 		// 如需多个测试，可以复制上方元素。
 	}
 
 	for _, q := range qs {
 		a, p := q.ans, q.para
-		
-		ast.Equal(a.one, p.one, "输入:%v", p)
+
+		ast.Equal(a.one, longestCommonPrefix(p.one), "输入:%v", p)
 	}
 }