#include <stdio.h>
#include <string.h>
int myatoi(char *s, int l, int base);
int main(int argc, char **argv)
{
	printf("Print your string number\n");
	char s[100]; scanf("%s", s);
	printf("Enter your string number base\n");
	int base;
	scanf("%d", &base);
	printf("Your converted number is %d\n",  myatoi(s, strlen(s), base));
	return 0;
}
int myatoi(char *s, int l, int base) 
{	
	int result = 0;
	int is_pos = 1;
	int symb;
	int d;
	for(int i=0; i < l; i++)
	{
		symb = (int)s[i];
		if((int)s[i]=='-')
			{
				is_pos = -1;
			}
		else if(base <= 10)
			{
				if((int)s[i] < '0' || (int)s[i] > '9')
				{
					printf("Not a number\n");
					result = 0;
					break;
				}	
				result = result * base + ((int)s[i] - '0');
			}
		else
			{
				if (symb >= '0' && symb <= '9') 
				{
					d = symb - '0';
				}
				else if (symb >= 'A' && symb <= 'Z') 
				{
					d = symb - 'A' + 10;
				} 
				else if (symb >= 'a' && symb <= 'z') 
				{
					d = symb - 'a' + 10;
				}
				result = result * base + d;
			}
        
	}
	result = result * is_pos;
	return result;
}