sum_of_primes_upto_n.py

// C++ program to find sum of primes in
// range from 1 to n.
#include <bits/stdc++.h>
using namespace std;
 

int sumOfPrimes(int n)
{
    // Array to store prime numbers
    bool prime[n + 1];
    memset(prime, true, n + 1);
 
    for (int p = 2; p * p <= n; p++) {
 
        // If prime[p] is not changed, then
        // it is a prime
        if (prime[p] == true) {
 
            // Update all multiples of p
            for (int i = p * 2; i <= n; i += p)
                prime[i] = false;
        }
    }
 
    // Return sum of primes generated through
    // Sieve.
    int sum = 0;
    for (int i = 2; i <= n; i++)
        if (prime[i])
            sum += i;
    return sum;
}
 
// Driver code
int main()
{
    int n ;
    cin >> n;
    cout << sumOfPrimes(n);
    return 0;
}