#include <stdio.h>
int main()
{
    char hex[17];
    int i = 0, val,decimal,len;
    decimal = 0;
    printf("Enter any hexadecimal number: ");
    gets(hex);
    len = strlen(hex);
    len--;
    for(i=0; hex[i]!='\0'; i++)
    {
        if(hex[i]>='0' && hex[i]<='9')
        {
            val = hex[i] - 48;
        }
        else if(hex[i]>='a' && hex[i]<='f')
        {
            val = hex[i] - 97 + 10;
        }
        else if(hex[i]>='A' && hex[i]<='F')
        {
            val = hex[i] - 65 + 10;
        }

        decimal += val * pow(16, len);
        len--;
    }

    printf("Hexadecimal number = %s\n", hex);
    printf("Decimal number = %d", decimal);

    return 0;
}