Sieve of eresthossis cp c++

int n;
vector<char> is_prime(n+1, true);
is_prime[0] = is_prime[1] = false;
for (int i = 2; i <= n; i++) {
    if (is_prime[i] && (long long)i * i <= n) {
        for (int j = i * i; j <= n; j += i)
            is_prime[j] = false;
    }
}

Source: cp-algorithms.com

Similar codes

0 vote120 views1 answer
Varint index
C++
0 vote127 views1 answer
Cpp get keystroke in console only
C++
0 vote127 views1 answer
Why we use iostream in C++ programming
C++
3 votes121 views1 answer
Convert refference to pointer c++
C++
-1 vote89 views1 answer
How to insert all values from one vector to another
C++
0 vote127 views1 answer
How to type cast quotient of two integers to double with c++
C++
0 vote127 views1 answer
How to complie c++ to spesific name using terminal
C++
2 votes128 views1 answer
Pointer dereference
C++
0 vote180 views2 answers
Total sales in array c++ two dimensional array
C++
3 votes134 views2 answers
Define and show the implementation of the functions of an arrayList.
C++