/* compute response to Alcatel challenge */
#include <stdio.h>

#define M       0x5c22db93
#define BIT31   (1<<31)
#define MASK    0xffffffff


unsigned int image(char *s) {
        int i, j, b = ~0;

        for (i = 0; s[i]; i++) {
                for (j = 7; j >= 0; j--) {
                        b = ((b & BIT31) ? ((b<<1)^M) : (b<<1));
                        if (s[i] & (1<<j))
                                b ^= M;
                }
        }
        return ~b & MASK;
}

int main(int argc, char **argv) {
        if (argc == 2)
                printf("%s: %u\n", argv[1], image(argv[1]));
        return 0;
}