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javarangeprimes

what is wrong with the code as i am unable to print 3 and 2

I am unable to get all the prime numbers printed .can someone help me with this .I get all the values except 2 and 3 . It starts with 5 .

public static void primesinRange(int n) {
  int flag=1;
  int i, j=2;
  
  for(i=2;i<=n;i++) { 
    if(n==1 || n==0) {
           continue;
    }

    if(n==2) {
      flag=1;
      continue;
    }

    flag=1;

    for(j=2;j<=Math.sqrt(n);j++) { 
      if((i%j)==0) {
        flag=0;
        break;
      }
    } 
        
    if(flag==1) {
      System.out.print(i+ " ");
    }  
  }   
}
Solution

  • You need to change the condition of your inner for-loop from

    j<=Math.sqrt(n)

    to

    j<=Math.sqrt(i)

    Otherwise for sufficiently large values of n this range will include the small i values.