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  1. #include <bits/stdc++.h>
  2. using namespace std;
  3. #define int              long long int
  4. #define double           long double
  5. #define print(a)         for(auto x : a) cout << x << " "; cout << endl
  6.  
  7.  
  8. const int M = 1000000007;
  9. const int N = 3e5+9;
  10. const int INF = 2e9+1;
  11. const int LINF = 2000000000000000001;
  12.  
  13. inline int power(int a, int b, int mod=M) {
  14.     int x = 1;
  15.     a %= mod;
  16.     while (b) {
  17.         if (b & 1) x = (x * a) % mod; 
  18.         a = (a * a) % mod;
  19.         b >>= 1;
  20.     }
  21.     return x;
  22. }
  23.  
  24.  
  25. //_ ***************************** START Below *******************************
  26.  
  27.  
  28.  
  29.  
  30. vector<int> isPrime;
  31.  
  32.  
  33. //* Basic : No multiplication Overflow 
  34. void seive1(){
  35.     isPrime.assign(N+1, 1);
  36.     isPrime[0] = isPrime[1] = 0;
  37.  
  38.     for(int i = 2; i<=N; i++){
  39.         if(isPrime[i] == 0) continue;
  40.  
  41.         for(int j=2*i; j<=N; j+=i){
  42.             isPrime[j] = 0;
  43.         }
  44.     }
  45. }
  46.  
  47.  
  48.  
  49. //* Time Optimized Seive : i*i ==> may overflow
  50. void seive2(){
  51.  
  52. 	isPrime.assign(N+1, 1);
  53. 	isPrime[0] = isPrime[1] = 0;
  54.  
  55. 	for(int i = 2; i*i<=N; i++){
  56. 		if(isPrime[i] == 0) continue;
  57.  
  58. 		for(int j=i*i; j<=N; j+=i){
  59. 			isPrime[j] = 0;
  60. 		}
  61. 	}
  62.  
  63. }
  64.  
  65.  
  66.  
  67.  
  68. void consistency(int n){
  69.  
  70. 	for(int i=1; i<=n ; i++){
  71. 		if(isPrime[i] ) cout << i << ", ";
  72. 	}cout << endl;
  73. }
  74.  
  75.  
  76.  
  77.  
  78. void solve() {
  79.  
  80. 	static bool initialized = []() {
  81.         seive1(); 
  82.         return true;
  83.     }();
  84.  
  85. 	static int _ = (seive2(), 0);
  86.  
  87.  
  88.  
  89. 	int n;
  90. 	cin >> n;
  91.  
  92. 	consistency(n);
  93.  
  94. }
  95.  
  96.  
  97.  
  98.  
  99.  
  100. int32_t main() {
  101.     ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
  102.  
  103.     int t = 1;
  104.     // cin >> t;
  105.     while (t--) {
  106.         solve();
  107.     }
  108.  
  109.     return 0;
  110. }
Success #stdin #stdout 0.01s 5460KB
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https://ideone.com/8B7hAi
language:
C++14 (gcc 8.3)
created:
18 hours ago
visibility:
public

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