C++ :

#include <iostream>
using namespace std;
int main() {
    char ch;
    char str[100];
    cin >> ch;
    cin.ignore();
    cin.getline(str, 100);
    int i = 0;
    bool found = false;
    while (str[i] != '\0') {
        if (str[i] == ch) {
            found = true;
            break;
        }
        i++;
    }
    if (found) {
        cout << "存在" << endl;
    } else {
        cout << "不存在" << endl;
    }
    return 0;
}