programming-examples/c++/11_Numerical_Problems/C++ Program to Implement Sieve of Eratosthenes.cpp

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2019-11-15 12:59:38 +01:00
/*This C++ program to implement Sieve of Eratosthenes. The program initializes an integer array with all the elements initialized to 0. Then the algorithm follows where the each non-prime elements index is marked as 1 inside the nested loops. The prime numbers are those whose value of index is marked as 0.*/
/*
* C++ Program to implement Sieve of Eratosthenes
*/
#include <iostream>
const int len = 100;
int main()
{
int arr[100] = {0};
for (int i = 2; i < 100; i++)
{
for (int j = i * i; j < 100; j+=i)
{
arr[j - 1] = 1;
}
}
for (int i = 1; i < 100; i++)
{
if (arr[i - 1] == 0)
std::cout << i << "\t";
}
}
/*
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