Sn=a+aa+aaa+aaaa+aaaaa的前5项之和，其中a是一个数字

#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<math.h>
int Multiply(int a,int b)
{
int sum = 0;
for (int i = 1; i <= b; i++)
{
sum += a;
a = a * 10 + a % 10;
}
return sum;
}
int main()
{
int num = 0;
printf(“请输入一个整数”);
scanf("%d", &num);
printf("%d\n",Multiply(num,5));
system(“pause”);
return 0;
}