#include <iostream>

using namespace std;

int atoi(char* s)

{

	int retval=0;

	int n=1;

	if (*s=='-')

	{

		n=-1;

		s++;

	}

	while (*s!='\0')

	{

		retval=retval*10+(*s-'0');

		s++;

	}

	return(n*retval);

}

void main()

{

	char s[6];

	long n;

	printf("Enter a string:\n") ;

	gets(s);

	n = atoi(s);

	printf("%ld\n",n);

	while(1);

}