7.5
#include <iostream> using namespace std; long jiecheng(int); void main75() { cout<<"Please enter the number:"; int n; while(cin>>n) { long result=jiecheng(n); cout<<"the result of jiecheng "<<n<<"! = "<<result<<endl; cout<<"Please enter the number :"; } system("pause"); } long jiecheng(int n) { if(n==0) return 1; else return n=n*jiecheng(n-1); }