https://www.nowcoder.com/practice/a35ce98431874e3a820dbe4b2d0508b1?tpId=37&tqId=21224&rp=1&ru=%2Fexam%2Foj%2Fta&qru=%2Fexam%2Foj%2Fta&sourceUrl=%2Fexam%2Foj%2Fta%3FtpId%3D37&difficulty=undefined&judgeStatus=undefined&tags=&title=&dayCountBigMember=%E8%BF%9E%E7%BB%AD%E5%8C%85%E6%9C%88

#include<iostream>
#include<algorithm>
#include<ccstring>
#include<string>

int main(){
    string s;
    char c;
    getline(cin,s);                 //读入字符串
    cin >> c;                       //读入字符
    c = tolower(c);                //将字符转换成其大写或小写
    transform(s.begin(),s.end(),s.begin(),::tolower);  //将字符串的大小写统一
    int res = 0;
    for(int i = 0;i<s.size();i++){
        if(s[i] == c)res++;
    }

    printf("%d",res);
    return 0;
}