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-rw-r--r--math/primeSieve.cpp24
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