Given a date, return the corresponding day of the week for that date.
The input is given as three integers representing the day, month and year respectively.
Return the answer as one of the following values {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"}.
Example 1:
Input: day = 31, month = 8, year = 2019 Output: "Saturday"
Example 2:
Input: day = 18, month = 7, year = 1999 Output: "Sunday"
Example 3:
Input: day = 15, month = 8, year = 1993 Output: "Sunday"
Constraints:
- The given dates are valid dates between the years
1971and2100.
Solution: LeapYear
Time complexity: O(1)
Space complexity: O(1)
C++
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// Author: Huahua inline bool leapYear(int y) { return (y % 4 == 0 && y % 100 != 0) || (y % 400 == 0); } class Solution { public: string dayOfTheWeek(int day, int month, int year) { vector<string> names = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"}; vector<int> days = {31, 28 + leapYear(year), 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; int sum = 0; for (int i = 1970; i < year; ++i) sum += 365 + leapYear(i); for (int i = 1; i < month; ++i) sum += days[i - 1]; sum += day; return names[(sum + 3) % 7]; } }; |