PAT1049

#include<stdio.h>

int count(int x)
{
	int sum=0;
	int base=1;
	while(x>=base)
	{
		int low=x%base;//低位数值 
		int high=x/(base*10);//高位数值 
		int digit=x%(base*10)/base;//正在处理位 
		if(digit==0)
			sum+=high*base;
		else if(digit==1)
			sum+=high*base+low+1;
		else 
			sum+=(high+1)*base;
		base*=10;
	}
	return sum;
}

int main()
{
	int n;
	scanf("%d",&n);
	printf("%d\n",count(n));
	return 0;
}