@root 为什么不对????????????

#include <bits/stdc++.h> using namespace std; int main() { long long a, b; char c; cin >> a >> b >> c; if (c != '+' && c != '-' && c != '' && c != '/') cout << "Invalid operator!"; else if (b == 0) cout << "Divided by zero!"; else if (c == '+') a = a + b; else if (c == '-') a = a - b; else if (c == '') a = a * b; else if (c == '/') a = a / b; cout << a; }