Time is added or subtracted, and how is time added?

date class: public int getdate() returns int type.

It can be like this: date=;

Then check whether the date is greater than the maximum value of the month;

Yes: Month plus 1; Determine whether the month is greater than 12;

If yes: plus 1 year.

Calender class, add(), look at the API!

add(int field, int amount) method!

It's best to use.

calendar cl=;

long cltemp=;

date is the time now plus the time in 7 days * date date=;

Time addition: Time is in 60 base.

Example: 2 hours, 48 minutes, 30 seconds + 1 hour, 21 minutes, 58 seconds = 4 hours, 10 minutes, and 28 seconds.

Explanation: 30 seconds + 58 seconds = 88 seconds = 1 minute 28 seconds So advance 1 minute to the minute.

48 minutes + 21 minutes + 1 minute = 70 minutes = 1 hour 10 minutes So advance 1 hour to the hour.

2 hours + 1 hour + 1 hour = 4 hours.

So: 2 hours, 48 minutes, 30 seconds + 1 hour, 21 minutes, 58 seconds = 4 hours, 10 minutes, and 28 seconds.

Dates cannot be added, but they can be subtracted, as follows:

1.First, count the number of days between two dates.

In excel, you can get the number of days between two dates by subtracting two dates directly, as shown in the following figure:

2.Calculating the number of days between two dates can also be done with the hidden function datedif function, which is as follows:

datedif(a2,b2,"d")。

Introduction to function knowledge:

The syntax of this function is as follows: =datedif(start date, end date, third parameter), and the third canopy parameter can have several cases, which can return the number of days, months, and years of the interval, respectively.

4.Let's take a look at how time is calculated.

First of all, the simplest thing is to directly subtract the two times to get the time difference. Note, however, that the cells where the results are stored are set to time format.

5.In the above example, if the time is less than 1 day, if the time exceeds 1 day, it can be directly subtracted using the above method.

6.The above example is more common in the timesheet time calculation, because the two dates may span 2 days or more, the default display result is incorrect, and the normal time difference needs to be displayed by formatting the cells. As shown below, format the cell as "[h]:

mm:ss", where h plus square brackets can be used to completely display the difference in hours of time, and if there is no square brackets, only the difference between hours after deducting days can be displayed.

7.If you want to display both the number of days and the time of the time difference, you can format the cells as:

d day h hour mm minute ss second.

Time addition: Time is in 60 base.

Example: 2 hours, 48 minutes, 30 seconds + 1 hour, 21 minutes, 58 seconds = 4 hours, 10 minutes, 28 seconds, explanation: 30 seconds + 58 seconds = 88 seconds = 1 minute 28 seconds So advance 1 minute 48 minutes + 21 minutes + 1 minute = 70 minutes = 1 hour and 10 minutes So advance 1 hour 2 hours + 1 hour + 1 hour = 4 hours to the hour.

So: 2 hours, 48 minutes, 30 seconds + 1 hour, 21 minutes, 58 seconds = 4 hours, 10 minutes, and 28 seconds.

1. Open the excel** that needs to add and sum the time.

2. Right-click the cell behind the total time and find the format of the unit.

3. Click Format the unit and find Custom under the number.

4. Click Custom, find H:mm, and click OK.

5. Then click Auto Sum in the formula and select the region that requires sum.

6. Then click the Enter key, you can see that the automatic sum of time has been generated, and the time addition calculation is completed.

Time is added in units of 60, for example: 25 minutes plus 40 minutes equals 65 minutes, and 65 minutes is converted into hours is one hour and five minutes.

When the time is added, the units should be added in turn, that is, hours, minutes, and seconds should be added respectively, for example, the addition of 1 hour, 10 minutes, 20 seconds, and 2 hours, 15 minutes, and 30 seconds is equal to 3 hours, 25 minutes, and 50 seconds.

The addition or subtraction of time requires the use of the hexagesimal system, which is a base 60 base system. One hour equals 60 minutes, and one minute equals 60 seconds.

The number 60 has 12 factors, i.e., and 60, where and 5 are prime numbers. Because of the large number of factors, the number in sexagesimal is divisible by the majority of numbers; In other words, it can be broken down into different lengths of time, for example, one hour can be seen as two 30 minutes, three 20 minutes, four 15 minutes, etc. 60 is also the smallest number that is divisible from 1 to 6 at the same time.

Do you ask about addition in elementary school arithmetic or about the addition of electronic time?

The former is the addition of hours, minutes, and seconds respectively, then the sexagesimal system, and finally reduced to the form of hours, minutes and seconds;

The latter can be done like this, e.g. A1 is 09:00 A2 is 10:00 A3 is 08:00 A4 is 07:00 I want to add A5 input:

text(sum(a1:a4),"[hh]:mm") OK.

60 in increments. 25 minutes plus 40 minutes is one hour and five minutes.

It depends on what you're using it for, for example?

Time is divided into 12-hour and 24-hour clocks, and when the two times add up to exceed the maximum (12, or 24), the date is changed. For example, 10 + 15 = 25 If it is 12 hours, then 25 divided by 24 rounded is the number of days, and the remainder of 25 to 12 is not enough hours for the whole day. For example.

Today is November 8th at 10:00 plus 15 hours, then the time becomes November 9th at 1 o'clock.

Time is not in decimal system, one hour is 60 minutes, one hour ago, 52 minutes, eight minutes. It is calculated as follows.

Divide 10:25 into 9:85 and subtract again.

Time addition and subtraction:

Time is in the base of 60.

Example: 16:30-10:45 5 hours and 45 minutes.

Explain, when 30 minutes is not enough to subtract 45 minutes, borrow 1 as 60 forward; Then it's 30+60-45 for 45 minutes.

16 was borrowed 1, leaving 15-10 5 hours; So the answer is: 5 hours and 45 minutes.

In Excel**, you can subtract two dates by using the days function, and the specific operation method is as follows:

Tools Raw materials: Maling Mechanical Revolution S3 Pro, Windows10, Excel 20212108

1. Input function.

Open the excel sheet, enter two dates, and enter the function name "days" in the third cell.

2. Select a date.

Select the end date and start date at the end of the function, separated by a comma between the middle mold dates.

3. Check the results.

Press enter and calculate the number of days between the two dates.

1.The first thing we need to know is that the datedif function is a hidden function in Excel, and its function is used to calculate the time difference. Also, the trade-off for this function is not rounded, but rounded down.

2.First we need a **, as an example in the following figure, we enter =datedif(A1,A2,) in cell C2"y")。It's important to note that this thing represents the difference between two vintages.

3.Then we select the cell C4 and enter =datedif(A1,A2,"m"It is important to note that m is the difference between the months in the two years.

4.Select cell C6 and enter =datedif(A1,A2,"d"), where d is the difference between the number of days in two years.

Hours and minutes are subtracted.

1.Let's use the following ** to show you the subtraction between hours and the subtraction between minutes.

2.We select cell d2 and enter =(a2-a1)*24. It should be noted that between the small tens, the subtraction is to directly subtract the number of days and multiply it by 24 hours to get the number of hours.

3.Select cell d3 and input =(A2-A1)*24*60, which means that the difference between hours is multiplied by 60 to become the difference between minutes.

4.Select cell E2 and enter =text(A2-A1,"[h]:m"It should be noted that this time we are using the time notation, which is in the format of "hours:minutes".

5.Select cell E3 and enter =text(A2-A1,"[m]"This method converts the hours in the time coefficient method directly to minutes.

The various times correspond to date series values, which can be subtracted directly and then returned to the corresponding format as needed.

It can be written as: ="2021-1-28 19:30"-"2020-1-28 18:10"

The result is days = 366 days, 1 hour and 20 minutes.

int("2021-1-28 19:30"-"2020-1-28 18:10"& days and hours mm")

Calculate how many days from now in the next day = datedif(now(),2021 02 12","d")

Calculate how many days from a certain day in the past = datedif ("2021/01/01",now(),d")

In Excel, time can be added or subtracted directly.