diff -r d0d940cdc8e2 -r dd57dce3529a r0/r.cpp
--- a/r0/r.cpp  Sat Dec 06 00:20:57 2014 +0900
+++ b/r0/r.cpp  Sat Dec 06 02:44:57 2014 +0900
@@ -181,11 +181,12 @@
        uint64_t total_ave = 0;

        for (int j = 0; j < TRANS_NUM; j++) {
+       retry:
            LONG res = card.transmit(command, commandlen);
            if (res != SCARD_S_SUCCESS) {
                std::fprintf(stderr, "retry: SCardTransmit(): %d\n", i);
                milliSleep(10);
-               continue;
+               goto retry;
            }
 //         std::fprintf(stderr, "%4u: %"PRIu64"\n", j, card.elapsed());
            total_ave += card.elapsed();
@@ -242,7 +243,7 @@
 static void number2code(char *out, uint32_t x)
 {
    static const char tbl[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
-   const int n = sizeof(tbl);
+   const int n = sizeof(tbl) - 1;
    int i = 0;
    while (x) {
        out[i++] = tbl[x % n];