题解 | #计算某字符出现次数#

#include <iostream>
using namespace std;

int main() {
    string s;
    char s1[2];
    char s1_change[2];
    int num=0;
    getline(cin,s);
    cin>>s1;
    if (s1[0]>='a' && s1[0]<='z') {
        s1_change[0]=s1[0]-32;
    } else {
        if (s1[0]>='A' && s1[0]<='Z') {
            s1_change[0]=s1[0]+32;
        } else {
            s1_change[0]=s1[0];
        }
    }

    for (int i=0; i<s.size(); i++) {
        if (s[i]==s1[0] || s[i]==s1_change[0]) {
            num++;
        }
    }
    cout<<num<<endl;
}

// 64 位输出请用 printf("%lld")