提交时间:2026-01-04 15:22:52
运行 ID: 80580
#include <iostream> #include <string> using namespace std; int main() { string input; cin >> input; for (char &c : input) { if (islower(c)) c = toupper(c); else if (isupper(c)) c = tolower(c); } cout << input << endl; return 0; }