To find the day of the week for any given date.
1. Take the last two figures of the year, add one-fourth of them
(neglecting remainder). Thus: 1949 = 49 + 12 = 61.
2. Add for the month, if for January or October, 1; May, 2; August, 3;
February, March, or November, 4; June, 5; September or December, 6;
April or July, 0; if leap year (that is, if it be divisible by 4 without
remainder) January 0; February 3.