Sieve Of Eras basic.cpp

#include<bits/stdc++.h>      // "Hello there"
using namespace std;


//  ->uncomment for ordered set                                     
// #include <ext/pb_ds/assoc_container.hpp>    
// #include <ext/pb_ds/tree_policy.hpp>     
// using namespace __gnu_pbds;
// // typedef tree<pair<int, int>, null_type, less<pair<int, int>>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;   // for pair
// typedef tree<int , null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;

//  ->uncomment for unordered map of pairs.

// #include<functional>        
// template <typename T>
// inline void hash_combine(std::size_t &seed, const T &val) {seed ^= std::hash<T>()(val) + 0x9e3779b9 + (seed << 6) + (seed >> 2);}
// template <typename T> inline void hash_val(std::size_t &seed, const T &val) {hash_combine(seed, val);}
// template <typename T, typename... Types>
// inline void hash_val(std::size_t &seed, const T &val, const Types &... args) {hash_combine(seed, val);    hash_val(seed, args...);}
// template <typename... Types>
// inline std::size_t hash_val(const Types &... args) {  std::size_t seed = 0; hash_val(seed, args...);return seed;}

// struct pair_hash
//  {   
//      template <class T1, class T2>
//     std::size_t operator()(const std::pair<T1, T2> &p) const 
//     {
//         return hash_val(p.first, p.second);
//     }
// };


 

#define pb push_back
#define ll long long int
#define SORTA(v) sort(v.begin(),v.end())
#define SORTD(v) sort(v.begin(),v.end(),greater<>())
#define endl '\n'
#define FOR(i,n) for(ll i = 0;i<n;i++)
#define FOR1(i,n) for(ll  i=1;i<=n;i++)
#define FAST ios_base::sync_with_stdio(false); cin.tie(NULL);
#define REVERSE(s) reverse(s.begin(),s.end())
#define GCD(a,b) __gcd(a,b)
#define VFIND(v1,val) find(v1.begin() , v1.end() , val )
#define VFILL(v1 , val)   std::fill(v1.begin(), v1.end(), val);
#define ERASE(x) x.erase(unique(x.begin(),x.end()),x.end())

const int MOD = 1e9 + 7;
long long int INF = LLONG_MAX;




void DPM(map<ll,ll>m1)
{
    for(auto it = m1.begin();it!=m1.end();it++)
    {
        cout<<it->first<<" "<<it->second<<endl;
    }
    cout<<endl;
}
void DPV(vector<ll>v)
{
    FOR(i,v.size())cout<<v[i]<<" ";cout<<endl;
}
void DPS(set<ll>s1)
{
    for(auto it =s1.begin();it!=s1.end();it++)cout<<*it<<" ";cout<<endl;
}



ll dx[4] = { 0,0,1,-1 };
ll dy[4] = { 1,-1,0,0 };
string pos = "RLDU";

// check the limits dummy
const ll  NN = 3* (1e5) + 100;
int main()
{
    FAST;
    ll i ,j , TC = 1;
    //  cin>>TC;
 
    ll n = 1e6;
    vector<bool>prime(n+1);
    fill( prime.begin() , prime.end() , 1);


    for(i = 2; i*i <=n; i++)
    {
        if( prime[i] )
        {
            for(j = i*i; j<=n; j += i)
            {
                prime[j] = false;
            }
        }
    }
    

    ll t; cin>>t;

    FOR1(i,t)
    {
        if( prime[i] )cout<<i<<" ";
    }

    // n*log( log(n) )


}  





































// vector<vector<int>> vec( n , vector<int> (m, 0));  2d vector 
// to_string(a)
//  s1.substr(1,3) 3 char of s1 starting from 1   s1.sub(pos) starting from pos
// assic value of ('0'-'9') is(48 - 57) and (a-z) is (97-122) and (A-Z) is(65-90) and 32 for space
// reverse(v1.begin() + a , v1.begin() + b) reverse starting from a to b-1
// A lambda function is written like   [](argument1,argument2,.....){//code}
// to create unordered map for pairs unordered_map<pair<ll, ll>, ll, pair_hash> slopeCount;
// unordered_set<pair<ll, ll>, pair_hash> seen;