Лабораторная работа №1 / lab1 / hexAdd / hex2dec

#include <stdlib.h>
#include <string.h>
#include <stdio.h>

int hex(int j)
{
    int tmp=1;
    int i;
    for (i=0;i<j;i++)
	tmp=tmp*16;
    return tmp;
}

int main(int argc, char* argv[])
{
    int sum = 0;
    int temp, i;
    char* a;
  
	if(argc!=2)
	{
		printf("0\n");  
		return 2;
	}
    for (i=strlen(argv[1])-1; i>=0; i--)
    {
	if (argv[1][i]=='a')
        temp=10;
        else
	if (argv[1][i]=='b')
        temp=11;
        else
        if (argv[1][i]=='c')
        temp=12;
        else
        if (argv[1][i]=='d')
        temp=13;
        else
        if (argv[1][i]=='e')
        temp=14;
        else
        if (argv[1][i]=='f')
        temp=15;
        else if (argv[1][i]>='0' && argv[1][i]<='9')
        {
	    *a = argv[1][i];
	    temp = atoi(a);
	    //printf("%d\n",temp);
	}
	else
	{
	    printf("%i\n", 0);
	    return 1;
	}
	sum+=hex(strlen(argv[1])-i-1)*temp;
    }//for
    printf( "%i\n", sum);
    return 0;
}