過去的公曆上哪一天是十三號和星期五重合的？

維基百科上只有未來的，沒有過去的

判斷歷史上哪一天是星期幾的演算法：蔡勒公式_百度百科

根據此公式有代碼：

#include &

int test_day(int year, int month, int day)
{
if (month==1||month==2)
{
year--;
month+=12;
}
int c=year/100;
int y=year-c*100;
int week=(c/4)-2*c+(y+y/4)+(13*(month+1)/5)+day-1;
while (week &< 0) { week+=7; } week %= 7; return week == 5; } int main() { int year, month; for (year = 1800; year &<= 2015; year++) { for (month = 1; month &<= 12; month++) { if (test_day(year, month, 13)) { printf("%d-%02d-13 is Friday ", year, month); } } } return 0; }

可以列出1800年至今的所有13號是星期五的日期，結果如下：

1800-06-13 is Friday
1801-02-13 is Friday
1801-03-13 is Friday
1801-11-13 is Friday
1802-08-13 is Friday
1803-05-13 is Friday
1804-01-13 is Friday
1804-04-13 is Friday
1804-07-13 is Friday
1805-09-13 is Friday
1805-12-13 is Friday
1806-06-13 is Friday
1807-02-13 is Friday
1807-03-13 is Friday
1807-11-13 is Friday
1808-05-13 is Friday
1809-01-13 is Friday
1809-10-13 is Friday
1810-04-13 is Friday
1810-07-13 is Friday
1811-09-13 is Friday
1811-12-13 is Friday
1812-03-13 is Friday
1812-11-13 is Friday
1813-08-13 is Friday
1814-05-13 is Friday
1815-01-13 is Friday
1815-10-13 is Friday
1816-09-13 is Friday
1816-12-13 is Friday
1817-06-13 is Friday
1818-02-13 is Friday
1818-03-13 is Friday
1818-11-13 is Friday
1819-08-13 is Friday
1820-10-13 is Friday
1821-04-13 is Friday
1821-07-13 is Friday
1822-09-13 is Friday
1822-12-13 is Friday
1823-06-13 is Friday
1824-02-13 is Friday
1824-08-13 is Friday
1825-05-13 is Friday
1826-01-13 is Friday
1826-10-13 is Friday
1827-04-13 is Friday
1827-07-13 is Friday
1828-06-13 is Friday
1829-02-13 is Friday
1829-03-13 is Friday
1829-11-13 is Friday
1830-08-13 is Friday
1831-05-13 is Friday
1832-01-13 is Friday
1832-04-13 is Friday
1832-07-13 is Friday
1833-09-13 is Friday
1833-12-13 is Friday
1834-06-13 is Friday
1835-02-13 is Friday
1835-03-13 is Friday
1835-11-13 is Friday
1836-05-13 is Friday
1837-01-13 is Friday
1837-10-13 is Friday
1838-04-13 is Friday
1838-07-13 is Friday
1839-09-13 is Friday
1839-12-13 is Friday
1840-03-13 is Friday
1840-11-13 is Friday
1841-08-13 is Friday
1842-05-13 is Friday
1843-01-13 is Friday
1843-10-13 is Friday
1844-09-13 is Friday
1844-12-13 is Friday
1845-06-13 is Friday
1846-02-13 is Friday
1846-03-13 is Friday
1846-11-13 is Friday
1847-08-13 is Friday
1848-10-13 is Friday
1849-04-13 is Friday
1849-07-13 is Friday
1850-09-13 is Friday
1850-12-13 is Friday
1851-06-13 is Friday
1852-02-13 is Friday
1852-08-13 is Friday
1853-05-13 is Friday
1854-01-13 is Friday
1854-10-13 is Friday
1855-04-13 is Friday
1855-07-13 is Friday
1856-06-13 is Friday
1857-02-13 is Friday
1857-03-13 is Friday
1857-11-13 is Friday
1858-08-13 is Friday
1859-05-13 is Friday
1860-01-13 is Friday
1860-04-13 is Friday
1860-07-13 is Friday
1861-09-13 is Friday
1861-12-13 is Friday
1862-06-13 is Friday
1863-02-13 is Friday
1863-03-13 is Friday
1863-11-13 is Friday
1864-05-13 is Friday
1865-01-13 is Friday
1865-10-13 is Friday
1866-04-13 is Friday
1866-07-13 is Friday
1867-09-13 is Friday
1867-12-13 is Friday
1868-03-13 is Friday
1868-11-13 is Friday
1869-08-13 is Friday
1870-05-13 is Friday
1871-01-13 is Friday
1871-10-13 is Friday
1872-09-13 is Friday
1872-12-13 is Friday
1873-06-13 is Friday
1874-02-13 is Friday
1874-03-13 is Friday
1874-11-13 is Friday
1875-08-13 is Friday
1876-10-13 is Friday
1877-04-13 is Friday
1877-07-13 is Friday
1878-09-13 is Friday
1878-12-13 is Friday
1879-06-13 is Friday
1880-02-13 is Friday
1880-08-13 is Friday
1881-05-13 is Friday
1882-01-13 is Friday
1882-10-13 is Friday
1883-04-13 is Friday
1883-07-13 is Friday
1884-06-13 is Friday
1885-02-13 is Friday
1885-03-13 is Friday
1885-11-13 is Friday
1886-08-13 is Friday
1887-05-13 is Friday
1888-01-13 is Friday
1888-04-13 is Friday
1888-07-13 is Friday
1889-09-13 is Friday
1889-12-13 is Friday
1890-06-13 is Friday
1891-02-13 is Friday
1891-03-13 is Friday
1891-11-13 is Friday
1892-05-13 is Friday
1893-01-13 is Friday
1893-10-13 is Friday
1894-04-13 is Friday
1894-07-13 is Friday
1895-09-13 is Friday
1895-12-13 is Friday
1896-03-13 is Friday
1896-11-13 is Friday
1897-08-13 is Friday
1898-05-13 is Friday
1899-01-13 is Friday
1899-10-13 is Friday
1900-04-13 is Friday
1900-07-13 is Friday
1901-09-13 is Friday
1901-12-13 is Friday
1902-06-13 is Friday
1903-02-13 is Friday
1903-03-13 is Friday
1903-11-13 is Friday
1904-05-13 is Friday
1905-01-13 is Friday
1905-10-13 is Friday
1906-04-13 is Friday
1906-07-13 is Friday
1907-09-13 is Friday
1907-12-13 is Friday
1908-03-13 is Friday
1908-11-13 is Friday
1909-08-13 is Friday
1910-05-13 is Friday
1911-01-13 is Friday
1911-10-13 is Friday
1912-09-13 is Friday
1912-12-13 is Friday
1913-06-13 is Friday
1914-02-13 is Friday
1914-03-13 is Friday
1914-11-13 is Friday
1915-08-13 is Friday
1916-10-13 is Friday
1917-04-13 is Friday
1917-07-13 is Friday
1918-09-13 is Friday
1918-12-13 is Friday
1919-06-13 is Friday
1920-02-13 is Friday
1920-08-13 is Friday
1921-05-13 is Friday
1922-01-13 is Friday
1922-10-13 is Friday
1923-04-13 is Friday
1923-07-13 is Friday
1924-06-13 is Friday
1925-02-13 is Friday
1925-03-13 is Friday
1925-11-13 is Friday
1926-08-13 is Friday
1927-05-13 is Friday
1928-01-13 is Friday
1928-04-13 is Friday
1928-07-13 is Friday
1929-09-13 is Friday
1929-12-13 is Friday
1930-06-13 is Friday
1931-02-13 is Friday
1931-03-13 is Friday
1931-11-13 is Friday
1932-05-13 is Friday
1933-01-13 is Friday
1933-10-13 is Friday
1934-04-13 is Friday
1934-07-13 is Friday
1935-09-13 is Friday
1935-12-13 is Friday
1936-03-13 is Friday
1936-11-13 is Friday
1937-08-13 is Friday
1938-05-13 is Friday
1939-01-13 is Friday
1939-10-13 is Friday
1940-09-13 is Friday
1940-12-13 is Friday
1941-06-13 is Friday
1942-02-13 is Friday
1942-03-13 is Friday
1942-11-13 is Friday
1943-08-13 is Friday
1944-10-13 is Friday
1945-04-13 is Friday
1945-07-13 is Friday
1946-09-13 is Friday
1946-12-13 is Friday
1947-06-13 is Friday
1948-02-13 is Friday
1948-08-13 is Friday
1949-05-13 is Friday
1950-01-13 is Friday
1950-10-13 is Friday
1951-04-13 is Friday
1951-07-13 is Friday
1952-06-13 is Friday
1953-02-13 is Friday
1953-03-13 is Friday
1953-11-13 is Friday
1954-08-13 is Friday
1955-05-13 is Friday
1956-01-13 is Friday
1956-04-13 is Friday
1956-07-13 is Friday
1957-09-13 is Friday
1957-12-13 is Friday
1958-06-13 is Friday
1959-02-13 is Friday
1959-03-13 is Friday
1959-11-13 is Friday
1960-05-13 is Friday
1961-01-13 is Friday
1961-10-13 is Friday
1962-04-13 is Friday
1962-07-13 is Friday
1963-09-13 is Friday
1963-12-13 is Friday
1964-03-13 is Friday
1964-11-13 is Friday
1965-08-13 is Friday
1966-05-13 is Friday
1967-01-13 is Friday
1967-10-13 is Friday
1968-09-13 is Friday
1968-12-13 is Friday
1969-06-13 is Friday
1970-02-13 is Friday
1970-03-13 is Friday
1970-11-13 is Friday
1971-08-13 is Friday
1972-10-13 is Friday
1973-04-13 is Friday
1973-07-13 is Friday
1974-09-13 is Friday
1974-12-13 is Friday
1975-06-13 is Friday
1976-02-13 is Friday
1976-08-13 is Friday
1977-05-13 is Friday
1978-01-13 is Friday
1978-10-13 is Friday
1979-04-13 is Friday
1979-07-13 is Friday
1980-06-13 is Friday
1981-02-13 is Friday
1981-03-13 is Friday
1981-11-13 is Friday
1982-08-13 is Friday
1983-05-13 is Friday
1984-01-13 is Friday
1984-04-13 is Friday
1984-07-13 is Friday
1985-09-13 is Friday
1985-12-13 is Friday
1986-06-13 is Friday
1987-02-13 is Friday
1987-03-13 is Friday
1987-11-13 is Friday
1988-05-13 is Friday
1989-01-13 is Friday
1989-10-13 is Friday
1990-04-13 is Friday
1990-07-13 is Friday
1991-09-13 is Friday
1991-12-13 is Friday
1992-03-13 is Friday
1992-11-13 is Friday
1993-08-13 is Friday
1994-05-13 is Friday
1995-01-13 is Friday
1995-10-13 is Friday
1996-09-13 is Friday
1996-12-13 is Friday
1997-06-13 is Friday
1998-02-13 is Friday
1998-03-13 is Friday
1998-11-13 is Friday
1999-08-13 is Friday
2000-10-13 is Friday
2001-04-13 is Friday
2001-07-13 is Friday
2002-09-13 is Friday
2002-12-13 is Friday
2003-06-13 is Friday
2004-02-13 is Friday
2004-08-13 is Friday
2005-05-13 is Friday
2006-01-13 is Friday
2006-10-13 is Friday
2007-04-13 is Friday
2007-07-13 is Friday
2008-06-13 is Friday
2009-02-13 is Friday
2009-03-13 is Friday
2009-11-13 is Friday
2010-08-13 is Friday
2011-05-13 is Friday
2012-01-13 is Friday
2012-04-13 is Friday
2012-07-13 is Friday
2013-09-13 is Friday
2013-12-13 is Friday
2014-06-13 is Friday
2015-02-13 is Friday
2015-03-13 is Friday
2015-11-13 is Friday

註：此公式不適用於1582年10月15日之前的日期。