#include <iostream> #include <string> using namespace std; int main() { string str; cin >> str; int count[26] = {0}; // 统计每个字母出现的次数 for (char c : str) { if (c >= 'a' && c <= 'z') { count[c - 'a']++; } } int maxCount = 0; char maxChar = 'a'; for (int i = 0; i < 26; i++) { if (count[i] > maxCount) { maxCount = count[i]; maxChar = 'a' + i; } } cout << maxChar ; return 0; }