# include <stdio.h>
# include <string.h>
# define MAXN 80
/** metatropi enos opoioudipote arithmou apo string se noumero **/

/** epistrefei 1 an ola ta stoixeia tou x einai psifia **/
int allDigits(char x[])
{
	int i;
	if(strlen(x)==0) return 0;
	for(i=0;i<strlen(x);i++)
	{
		if(!(x[i]>='0' && x[i]<='9')) return 0;
	}
	return 1;
}

int ascii2int(char x[])
{
	int count=0;
	int i;
	for(i=0;i<strlen(x);i++)
	{
		count=10 * count + (x[i]-'0');
	}
	return count;
}

int main()
{
	char d[MAXN];
	int k;
	do
	{
		printf("Doste akeraio arithmo ?\n");
		gets(d);
	}while(!allDigits(d));
	k=ascii2int(d);
	printf("O arithmos einai %d \n",k);
	return 0;
}