计算星期几的C代码

by code)               */
    {31, "March ",     2},             /* 
March                                                        */
    {30, "April ",     5},             /* 
April                                                        */
    {31, "May ",       0},             /* 
May                                                          */
    {30, "June ",      3},             /* 
June                                                         */
    {31, "July ",      5},             /* 
July                                                         */
    {31, "August ",    1},             /* 
August                                                       */
    {30, "September ", 4},             /* 
September                                                    */
    {31, "October ",   6},             /* 
October                                                      */