#include<iostream>
#include<stdlib.h>
using namespace std;
int main()
{
freopen("123.txt","r",stdin);
freopen("abc.txt","w",stdout);
int a;
cin>>a;
cout<<a*2<<endl;
system("pause");
return 0;
}
#include<iostream>
#include<stdlib.h>
using namespace std;
int main()
{
freopen("123.txt","r",stdin);
freopen("abc.txt","w",stdout);
int a;
cin>>a;
cout<<a*2<<endl;
system("pause");
return 0;
}
转载于:https://www.cnblogs.com/hxsyl/archive/2012/06/11/2544858.html