Sieve of eratosthenes c

/******************************************************************************

                            Online C Compiler.
                Code, Compile, Run and Debug C program online.
Write your code in this editor and press "Run" button to compile and execute it.

*******************************************************************************/

#include <stdio.h>
#include <math.h>
#include <stdbool.h>

int main()
{
    int n,i,j; //declaring required variables
    scanf("%d",&n); //scanning n(limit numbers)
    bool arr[n+1]; //declaring an array which contains true and false values
    arr[1]=false; //setting the first index to false (1 is not a prime number)
    
    for(i=2;i<=n;i++){
        arr[i]=true; //we are assuming that all the numbers are true which means prime
    }
    
    for(i=2;i<sqrt(n)+1;i++){ //running loop to the sqrt on n + 1
        if(arr[i]==true){ //if the number is true of prime 
            for(j=i+i;j<=n;j+=i){ //run the loop to n
                arr[j]=false; //assume that the divisble numbers are not prime
            }
        }
    }
    
    for(i=2;i<=n;i++){
        if(arr[i]==true){
            printf("%d ",i); //printing the numbers if that is true 
        }
    }
    
    

    return 0;
}

Similar codes

1 vote171 views1 answer
Space after format specifiers in c
C
0 vote181 views3 answers
Script hack blox fruti
C
6 votes166 views1 answer
What is strikethrough in markdown
C
2 votes257 views1 answer
Mirzapur 2
C
0 vote179 views2 answers
C convert float to string
C
18 votes232 views3 answers
Read file c
C
0 vote198 views1 answer
Reading string with spaces in c
C
0 vote172 views1 answer
Phpunit assert continue
C
1 vote176 views4 answers
Array of strings c
C
1 vote205 views1 answer
Hi servicenow
C