在 Sakamoto 算法中查找 t[] 数组以查找星期几

Question

我想知道如何在这个算法中找到如何计算t[] 数组的值？

int dow(int y, int m, int d)        
{        

   static int t[] = {0, 3, 2, 5, 0, 3, 5, 1, 4, 6, 2, 4};        

   y -= m < 3;        

   return (y + y/4 - y/100 + y/400 + t[m-1] + d) % 7;        

}

Answer 1

可以使用code below来生成需要的数组

#include <stdio.h>

int main(void) {
    int arr[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
    int totalDaysInThisYear = -1, m;  /* Parity would make totalDaysInThisYear = 0 */
    for(m = 1; m <= 12; ++m) {
        const int parity = (m < 3);
        printf("%d\n", (totalDaysInThisYear + parity) % 7);
        totalDaysInThisYear+= arr[m - 1];
    }
    return 0;
}