• 位运算

func reverseString(s []byte)  {l := 0r := len(s) - 1for l < r {s[l] ^= s[r]s[r] ^= s[l]s[l] ^= s[r]l++r--}
}

• 没技巧

func reverseStringRange(s []byte, l int, r int) {if r >= len(s) {r = len(s) - 1}for l < r {s[l] ^= s[r]s[r] ^= s[l]s[l] ^= s[r]l++r--}
}
func reverseStr(s string, k int) string {res := []byte(s)count := 0for i := 0; i < len(s); i += 2 * k {reverseStringRange(res, i, i+k-1)count++}return string(res)
}

def isNumber(c):return c >= '0' and c <= '9's = input()
res = []
for c in s:res.append("number" if isNumber(c) else c)
print("".join(res))

func reverseStringArr(s []string) {l := 0r := len(s) - 1for l < r {temp := s[l]s[l] = s[r]s[r] = templ++r--}
}
func reverseWords(s string) string {chars := []byte(s)temp := ""var resArr []string// 分词for _, char := range chars {if char == ' ' {if temp != "" {resArr = append(resArr, temp)}temp = ""continue}temp = temp + string(char)}if temp != "" {resArr = append(resArr, temp)}// 反转reverseStringArr(resArr)// 拼接res := ""for i, s := range resArr {res += sif i != len(resArr)-1 {res += " "}}return res
}

• SB版

n = int(input(""))
s = input("")print(s[-n:]+s[:-n])

• NB版

n = int(input(""))
s = input("")r = len(s) - 1
reverse(s, 0, r-n)
reverse(s, r-n, r)
reverse(s, 0, r)
print(s[-n:]+s[:-n])