The problem solving process is as follows:

Method for calculating day of the week using extended data:

What is a certain day in history? What day is the future? There are many formulas for this problem (two general formulas and some piecewise formulas), among which Le Cai formula is the most famous. That is w = y+[y/4]+[c/4]-2c+[26 (m+1)1+d-1.

W: week; C: Century-1; Y: year (two digits); M: month (m is greater than or equal to 3, but less than or equal to 14, that is, in Chuller's formula, 1 and February in one year should be regarded as 13, and 14 in the previous year, for example, 1 in 2003 should be regarded as 2002. D: day; [] stands for rounding, that is, only the integer part is taken.

C is the number of centuries minus one, Y is the last two digits of the year, M is the month, and D is the number of days. 65438+ 10 and February are calculated according to the previous year's 65438+March and 65438+April, when C and Y are calculated according to the previous year.