Table of Contents

- 1 What is modulo in competitive programming?
- 2 What is meant by modulo 10?
- 3 What is modulo in Codechef?
- 4 What happens when you mod a number by 10?
- 5 How do you calculate fast exponent?
- 6 Why is modulo useful?
- 7 What is the 10^9+7 modulo in programming?
- 8 What are the advantages of working modulo in programming?
- 9 What is the modulo of (a*B*C) \%M?

## What is modulo in competitive programming?

The modulo operation is the same as ‘ the remainder of the division ‘. If I say a modulo b is c, it means that the remainder when a is divided by b is c. The modulo operation is represented by the ‘\%’ operator in most programming languages (including C/C++/Java/Python).

### What is meant by modulo 10?

Put simply, modulo is the math operation of finding the remainder when you divide two numbers together. If you are asking “what is 10 mod 10?” then what you really need to know is “what is the remainder when I divide 10 by 10?”.

#### What is modulo in Codechef?

Modulo is a much heavier operation than addition, subtraction, or even multiplication. Try to avoid using it when it’s not necessary. This is what the “fast addition” and “fast subtraction” is for. I generally use a as the number on the left side of the operation, and b as the number on the right (as in a + b).

**How do you calculate modulo 10?**

The modulo 10 is calculated from this sum. First the sum is divided by 10. The remainder of the division is subtracted from 10 (calculate the difference to 10). The result of this subtraction is the checksum/check digit.

**Is modulo operation associative?**

We have seem that addition and multiplica- tion modulo n are both commutative and associative, and that multiplication distributes over addition, as in ordinary integer arithmetic.

## What happens when you mod a number by 10?

where r is a common remainder. So, to put it simply – modulus congruence occurs when two numbers have the same remainder after the same divisor. So for example: 24 modulo 10 and 34 modulo 10 give the same answer: 4. Therefore, 24 and 34 are congruent modulo 10.

### How do you calculate fast exponent?

How can we calculate A^B mod C quickly for any B?

- Step 1: Divide B into powers of 2 by writing it in binary. Start at the rightmost digit, let k=0 and for each digit:
- Step 2: Calculate mod C of the powers of two ≤ B. 5^1 mod 19 = 5.
- Step 3: Use modular multiplication properties to combine the calculated mod C values.

#### Why is modulo useful?

Since any even number divided by 2 has a remainder of 0, we can use modulo to determine the even-ess of a number. This can be used to make every other row in a table a certain color, for example.

**What comes first division or modulo?**

The multiplication, modulus and division are evaluated first in left-to-right order (i.e., they associate from left to right) because they have higher precedence than addition and subtraction. The addition and subtraction are applied next.

**Why should I print my answer modulo 10^9 + 7?**

Printing your answer modulo (10^9 +7) ensures that it fits the maximum value your system is capable of storing in standard allotted space, preventing “integer overflow”, after which variables will begin to behave erratically, giving wrong answers. It is also consistent with the test code written by the question setter as well as case tester.

## What is the 10^9+7 modulo in programming?

In most programming competitions, we are required to answer the result in 10^9+7 modulo. The reason behind this is, if problem constraints are large integers, only efficient algorithms can solve them in an allowed limited time.

### What are the advantages of working modulo in programming?

1. Working modulo a large prime makes it likely that if your program produces the correct output, it actually did some calculation and did so correctly. 2. Working modulo 1,000,000,007 allows a large number of languages to use their built-in integer types to store and calculate the result.

#### What is the modulo of (a*B*C) \%M?

Method 1: First, multiply all the number and then take modulo: (a*b*c)\%m = (459405448184212290893339835148809 515332440033400818566717735644307024625348601572) \% 1000000007 a*b*c does not fit even in the unsigned long long int due to which system drop some of its most significant digits.