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#include <math.h>
// time: O(sqrt(n)) .. space: O(1)
bool isPrime(int n) {
if (n < 2) return false;
int iter = 2;
while(iter <= sqrt(n)) {
if (n % iter == 0) return false;
iter++;
}
return true;
}
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#include<iostream>
using namespace std;
int main()
{
int n;
bool c=1;
cin >> n;
if (n <= 1)
{
cout << "NO\n";
}
else
{
for (int i = 2; i < n; i++)
{
if (n % i == 0)
{
c=0;
break;
}
}
if (!c)
cout << "NO\n";
else
cout << "YES\n";
}
return 0;
}
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#include<iostream>
using namespace std;
bool isPrimrNumber(int number){
bool isPrimeFlag=true;
for(int i=2;i<number;i++){
if(number%i==0){
isPrimeFlag=false;
break;
}
}
return isPrimeFlag;
}
int main()
{
int number;
cout<<"Please enter your number";
cin>>number;
bool isPrimeFlag=isPrimeNumber(number)
if(isPrimeFlag)
{
cout<<"prime Number";
}
else
{
cout<<"not prime number";
}
}
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bool prime(int x) {
if (x == 2 || x == 3) return true;
if (x == 1 || x % 2 == 0 || x % 3 == 0) return false;
int k = -1;
while (k<=int(sqrt(x))) {
k+=6;
if (x % k == 0 || x % (k+2) == 0) break;
}
return k>int(sqrt(x));
}
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#include<iostream>
#include<cmath>
using namespace std;
int main(){
int n;
cin>>n;
for(int i=2;i<sqrt(n)+1;i++){
if(n%i==0){
cout<<"number is not a prime";
return 0;
}
}
cout<<"number is a prime";
return 0;
}
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// A optimized school method based C++ program to check
// if a number is prime
#include <bits/stdc++.h>
using namespace std;
bool isPrime(int n)
{
// Corner cases
if (n <= 1)
return false;
if (n <= 3)
return true;
// This is checked so that we can skip
// middle five numbers in below loop
if (n % 2 == 0 || n % 3 == 0)
return false;
for (int i = 5; i * i <= n; i = i + 6)
if (n % i == 0 || n % (i + 2) == 0)
return false;
return true;
}
// Driver Program to test above function
int main()
{
isPrime(11) ? cout << " true\n" : cout << " false\n";
isPrime(15) ? cout << " true\n" : cout << " false\n";
return 0;
}
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template<class T> bool isPrime(T n)
{
T i;
if(i<2) return false;
for(i = 2; i * i <= n; i++) {
if(n % i == 0) return false;
}
return true;
}
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#include <iostream>
using namespace std;
int checkPrime(int num)
{
if(num < 2){
return 0;
}
else{
int x = num/2;
for(int i = 2; i < x; i++)
{
if(num % i == 0)
{
return 0;
}
}
}
return 1;
}
int main()
{
int a = 1, b = 100;
for(int i=a; i <= b; i++){
if(checkPrime(i))
cout<<i<<" ";
}
return 0;
}
//Time Complexity: O(N^2)
//Space Complexity O(1)