2 // masashi shimakura 20140223
6 // 現在の年月で、一日前の日をかえす。(1 - 1 = 31)
7 int day_minus(int day_d)
13 if (day_d <= 0){ day = 1; }
14 else if(day_d > 31){ day = 31; }
18 switch(ctime_getr('m')){
19 case 1: ret = 31; break;
20 case 2: ret = 31; break;
22 switch(ctime_getr('y')){
23 case 2008: ret = 29; break;
24 case 2009: ret = 28; break;
25 case 2010: ret = 28; break;
26 case 2011: ret = 28; break;
27 case 2012: ret = 29; break;
28 case 2013: ret = 28; break;
29 default: ret = 28; break;
32 case 4: ret = 31; break;
33 case 5: ret = 30; break;
34 case 6: ret = 31; break;
35 case 7: ret = 30; break;
36 case 8: ret = 31; break;
37 case 9: ret = 31; break;
38 case 10: ret = 30; break;
39 case 11: ret = 31; break;
40 case 12: ret = 30; break;
41 default: ret = 31; break;
44 else{ ret = day - 1; }