CONVERSION BASE 2<==>10

#include <math.h> //pour pow

#define ASCIInumber 48

char str[31];

unsigned long BaseToDecimal(char string[])
{
    unsigned long value = 0;

    long i;

    for (i=0;i<=strlen(string)-1;i++)
        value = (value + string[i] - ASCIInumber) * 2;
    return value / 2;
}

int DecimalToBase(long n)
{
    int i = 0, j;

    for (j=0;j<=30;j++) str[j] = 0;

    while(pow(2,i) <= n) i++;

    if (!i) str[0] = ASCIInumber;

    while (n)
    {
        i--;
        str[i] = (n%2)+ASCIInumber;
        n = n / 2;
    }
}