#includeusing namespace std; int main() { int a , sum = 1; cout<<"请输入要求的数"; cin>>a; for(int i = 1 ; i <= a ; i++){ sum = sum * i; } cout<<"%d的阶乘为:"<

#includeusing namespace std; int main() { int a , sum = 1; cout<<"请输入要求的数"; cin>>a; for(int i = 1 ; i <= a ; i++){ sum = sum * i; } cout<<"%d的阶乘为:"<