gistfile1.c

void decode(void)
{
    int i, j, k, r, c;

    for (i = 0; i < N - F; i++) buffer[i] = ' ';
    r = N - F;
    while ((c = getbit(1)) != EOF) {
        if (c) {
            if ((c = getbit(8)) == EOF) break;
            fputc(c, outfile);
            buffer[r++] = c; r &= (N - 1);
        } else {
            if ((i = getbit(EI)) == EOF) break;
            if ((j = getbit(EJ)) == EOF) break;
            for (k = 0; k <= j + 1; k++) {
                c = buffer[(i + k) & (N - 1)];
                fputc(c, outfile);
                buffer[r++] = c;  r &= (N - 1);
            }
        }
    }
}