2 // masashi shimakura 20140223
10 char * char_mon(int mon)
14 case 0 : ret = "Jan"; break;
15 case 1 : ret = "Feb"; break;
16 case 2 : ret = "Mar"; break;
17 case 3 : ret = "Apr"; break;
18 case 4 : ret = "May"; break;
19 case 5 : ret = "Jun"; break;
20 case 6 : ret = "Jul"; break;
21 case 7 : ret = "Aug"; break;
22 case 8 : ret = "Sep"; break;
23 case 9 : ret = "Oct"; break;
24 case 10 : ret = "Nov"; break;
25 case 11 : ret = "Dec"; break;
26 default : ret = "Not!"; break;