App Inventor 2
Programming mobile phones with Android 
by App Inventor 2 - Juan Antonio Villalpando

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49.- Odd / Even. Multiple of 4. Divisors of a number.

ip49_even_odd

- Presentation.

- Even - Odd.

- We write a number and app answer whether it is even or odd.

- We use the operator module, it makes a division between two numbers, but what we get rest division.

- If to divide a number by 2, the remainder is zero, that is even, otherwise it is ODD.

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Design

- We put letters in Bold. The size: Fill to parent.
- The TextBox in "NumberOnly". FontSize: 30. Bold.
- The Button with Width and Height 60 pixel container.

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Blocks

Extension.

We can make a similar code where indicated if a year is a leap year or not.

The code would be similar to what we have seen, only in the modulo operator rather than put 2 put to 4.

If by dividing one year from 4 the remainder is zero, it means that this year is a leap year, otherwise it is not.

Remember that leap years are Olympic years.

Module: two numbers is divided and the remainder is taken. The remainder has the same sign as the denominator.
Remaining: two numbers is divided and the remainder is taken. The remainder has the same sign as the numerator.
Quotient: get the integer quotient without decimals.

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49B.- Divisors of a number.

ip49b_divisors

- Write a number and should give us the divisors of that number, separated by a hyphen.

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Design

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Blocks

- Introduce a number.
- When you press the button passes the TextBox to the variable number.
- Enter a loop that is performing an operation as many times as the number entered.

- In each execution of the loop, performs the module number from the current value of n.
- If the modulus (remainder of the division) is zero, the number n is divisible, in this case added to the text variable: dividers.
- At the end all the information of the dividers variable is set in the Label2.

- Note that the Variable dividers do this:

divisors = divisors join - join n

That is, the variable text divisors, is adding the new values ​​of divisors.

Loop

n loop starts from 1.
The code is done run that is inside.
When you just start again, but this time the value n is incremented by 1 and now is 2.
It is carried out again to execute code the value of n reaches to the end number