prime numbers code example

Example 1: prime numbers

2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41,
43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97 ...

Example 2: prime number

a number that is divisible only by itself and 1 (e.g. 2, 3, 5, 7, 11)
suppose a number 'n' it can be divided by if '1' and only by itself then it can be a prime number

Example 3: first prime numbers

#include<bits/stdc++.h>
using namespace std;
bool Is_Prime(long long x){
	if(x%2==0)return false;
	for(int i=3;i*i<=x;i+=2)
		if(x%i==0)return false;
	return true;
}
int main(){
	//first n prime numbers
	int n;
	cin>>n;
	int i=1;
	while(n--){
		while(!Is_Prime(++i));
		cout<<i<<" ";
	}
}

Example 4: prime numbers

A number only divisible by 1 and itself

Example 5: prime number

#include<bits/stdc++.h>
using namespace std;
bool Is_Prime(long long x){
	if(x%2==0)return false;
	for(int i=3;i*i<=x;i+=2)
		if(x%i==0)return false;
	return true;
}
int main(){
	long long x;
	cin>>x;
	if(Is_Prime(x))cout<<"Is Prime";
	else cout<<"Is not Prime";
}

Example 6: prime numbers from 1 to 100

// find all numbers prime java
public class IsNumberIsSimple {
       
        public static void main (String args[]) {
        
            for ( int i=0; i < 100; i++) {
              isNumberIsSimple(i);
            }     
        }   
        
        public void isNumberIsSimple(num){
        	for ( int i=2; i < num; i++) {
                  if ( num%i == 0) {
                          return;
                  }      
          	}
          	System.out.println("Very well! It's simple! " + num);   
        }
}

//1, 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97

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