公式:W= (d+2*m+3*(m+1)/5+y+y/4-y/100+y/400+1)%7
int cal(int y, int m, int d) {
if (m == 1 || m == 2) {
m += 12;
y--;
}
int w = (d + 2 * m + 3*(m + 1) / 5 + y + y / 4 - y / 100 + y / 400 + 1) % 7;
return w;
}
int cal(int y, int m, int d) {
if (m == 1 || m == 2) {
m += 12;
y--;
}
int w = (d + 2 * m + 3*(m + 1) / 5 + y + y / 4 - y / 100 + y / 400 + 1) % 7;
return w;
}