字符串碎片

s = input()
letter,num,sa = '',0,len(s)
for i in s:
    if letter!=i:
       num+=1
       letter=i
print("%.2f"%(sa/num))

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        String s = sc.nextLine();
        char[] arr=s.toCharArray();

        int cout =1;//碎片个数
        char pre=arr[0];
        for (int i=1;i<arr.length;i++){
            if (arr[i]!=pre){
                pre=arr[i];
                cout++;
            }
        }
        System.out.println(String.format("%.2f",(float) arr.length/cout));
    }
}

#include<stdio.h>
#include<iostream>
#include<iomanip>

using namespace std;

double countmany(string s, int count, int now, char last){
    if(now >= s.length()){
        return (double) s.length()/count;
    }else{
        if(s.at(now) != last){
            count += 1;
            last = s.at(now);
        }
        return countmany(s, count, now+1, last);
    }
}

int main(){
    string s;
    cin >> s;
    double res = countmany(s, 1, 1, s.at(0));
    if(s.empty()){
        return 0;
    }
    cout << fixed << setprecision(2) << res;
}