diff options
Diffstat (limited to 'math/primeSieve.cpp')
| -rw-r--r-- | math/primeSieve.cpp | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/math/primeSieve.cpp b/math/primeSieve.cpp new file mode 100644 index 0000000..9981981 --- /dev/null +++ b/math/primeSieve.cpp @@ -0,0 +1,24 @@ +#include <iostream> +#include <vector> + +vector<int> primeSieve(int n) { + vector<int> primes; + vector<bool> isPrime(n,true); + for(int i = 2; i < n; i+=2) { + if(i*i <= n) { + if(isPrime[i]) { + primes.push_back(i); + for(int j = 1; i*j < n; j++) { + isPrime[i*j] = false; + } + } + } + else { + if(isPrime[i]) + primes.push_back(i); + } + if(i == 2) + i--; + } + return primes; +}
\ No newline at end of file |
