add 'Longest Common Prefix'

tags/string/longestCommonPrefix/main.go

@@ -0,0 +1,60 @@
+package main
+
+import "fmt"
+
+func main() {
+	var strs []string
+
+	strs = []string{}
+	fmt.Println(longestCommonPrefix(strs))
+
+	strs = []string{"a"}
+	fmt.Println(longestCommonPrefix(strs))
+
+	strs = []string{"a", "b"}
+	fmt.Println(longestCommonPrefix(strs))
+
+	strs = []string{"flower", "flow", "flight"}
+	fmt.Println(longestCommonPrefix(strs))
+
+	strs = []string{"dog", "racecar", "car"}
+	fmt.Println(longestCommonPrefix(strs))
+
+	strs = []string{"a", "abc", "ac"}
+	fmt.Println(longestCommonPrefix(strs))
+
+	strs = []string{"abcdef", "abc", "ab"}
+	fmt.Println(longestCommonPrefix(strs))
+
+	strs = []string{"ab", "abcdef", "abc", "ab"}
+	fmt.Println(longestCommonPrefix(strs))
+}
+
+func longestCommonPrefix(strs []string) string {
+	var res string
+	var char string
+	var mark bool
+	if len(strs) == 0 {
+		return ""
+	}
+	for i := 0; i < len(strs[0]); i++ {
+		char = strs[0][i : i+1]
+		mark = true
+		for j := 0; j < len(strs); j++ {
+			var str = strs[j]
+			if i > len(str)-1 {
+				mark = false
+				break
+			}
+			if str[i:i+1] != char {
+				mark = false
+				break
+			}
+		}
+		if !mark {
+			break
+		}
+		res += char
+	}
+	return res
+}