# C++ Program to Implement Euler Theorem

C++Server Side ProgrammingProgramming

This is a C++ Program which demonstrates the implementation of Euler Theorem. The number and modular must be coprime for the modular multiplicative inverse to exist.

## Algorithm

Begin
Take input to find modular multiplicative inverse
Take input as modular value
Perform inverse array function:
modInverse(x + 1, 0);
modInverse = 1;
for i = 2 to x
modInverse[i] = (-(y / i) * modInverse[y mod i]) mod y + y
return modInverse
End

## Example Code

#include <iostream>
#include <vector>
using namespace std;
vector<int> inverseArray(int x, int y) {
vector<int> modInverse(x + 1, 0);
modInverse = 1;
for (int i = 2; i <= x; i++) {
modInverse[i] = (-(y / i) * modInverse[y % i]) % y + y;
}
return modInverse;
}
int main() {
vector<int>::iterator it;
int a, m;
cout<<"Enter number to find modular multiplicative inverse: ";
cin>>a;
cout<<"Enter Modular Value: ";
cin>>m;
cout<<inverseArray(a, m)[a]<<endl;
}

## Output

Enter number to find modular multiplicative inverse: 26
Enter Modular Value: 7
7