S=a+aa+aaa+.........+a.....a

//S=a+aa+aaa+.........+a.....a;a属于集合{1,2,3,4,5,6,7,8,9}

#include <iostream.h>

#include<stdio.h>

void main()

{

int a,i,n,S=0;

cout<<"请输入a值: ";

cin>>a;

cout<<"请输入n值: ";

cin>>n;

for(i=1;i<=n;i++)

S=S*10+i*a;

cout<<"所求结果为: "<<S<<endl;

}