java - Boolean Array NullPointerException -

-

This question is already an answer here

  • 3 answers

I create one The program that is trying to generate two major numbers between the two given integers (A and B) for the T cases, I am implementing the prime living of the ereothinithy. My code is below I have read that the code mentioned in the code Line NullPointerException me a result of not start Boolean array. However, I thought I did this here: 

  boolean [] n = new boolean [b1];

Therefore, I'm confused as to why this exception is being thrown. I do not know any other possible reason why my code is wrong with

My error and input: 

  1 1 5 PrimeNumberFinder.main (Exception in formula on PrimeNumberFinder " Main "java.lang.NullPointerException .Java: 27)

My code: 

  class PrimeNumberFinder {public static void (string [] args) {scanner Scheduled Caste = new scanner (in system.); // Read the number of cases of expected problem from the input int t; = Sc.nextInt (); // Read the entire search for prime between each item (Ent I = 1; i & lt; = T; i ++) {// Par A = sc.nextInt (); Int B = sc.nextInt (); // Stitch Boolean [] N = According to the new Boolean [B1], create boolean array to store primes; // Set all values ​​to true (int j = 2; j & lt; = b; j ++) {n [j] = true; } // test for the prime number for all the elements of 'n' (integer k = 2; k * k; l; b = k; k ++) {if (n [k]) {(int l = For Kashmir, L * K & lt; = B, L ++] {N * L * K] = Wrong; (A, B) for print (Int M = A, M & LT; = B; M ++) {// This is the line (below) for which error appears. : NullPointerException if (n [m]) {System.out.println (m); } And {continue; }} System.out.println (""); }}

You have created an array of Boolean objects , But these are all started on null you obviously start most elements on true , but only starting with index 2 We do.

The line with NPE is assuming: 

  if (n [m]) {  
  m  starts with  a  which appears  1  based on the input given by you. But it never started. The number  1  is neither principal nor composite, so you should manage this matter separately.

Comments

Post a Comment

Popular posts from this blog

import - Python ImportError: No module named wmi -

-
I followed the instructions for downloading WMI for Python When I try to run the code for C.Win32_Service (StartMode = "Auto", state = "Stopped") import wmi c = wmi.WMI (): if Raw_input ("restart% s?"% S.Caption) .upper () == "Y": s.StartService () I got the error < Code> traceback (most recent call end): file ". \", Line 1, edit: I am using Python 2.7.6 EDIT2: I am running 64-bit Windows 2008 R2, and I've downloaded WMI-1.4.9.zip (md5). I removed the content and put it in D: Python \ Tools \ Scripts I executed dragon setup.py.install I said D : \ Python \ tools \ scripts to% PATH% and when I execute the code for C.Win32_Service (StartMode = "Auto", state = "Stopped") import wmi c = Wmi.WMI (): If raw_input ("Restart% s?"% S. Caption). () == "Y": s.StartService () error me Gets traceback (most recent call final): File ". See \", line 1, &
Read more

Editing Python Class in Shell and SQLAlchemy -

-
I am working on the terminal on a shell script after this tutorial SQLAlchemy tutorial. I need to type gt; & Gt; & Gt; Sqlalchemy import column, integer, string & gt; & Gt; & Gt; Class user (base): __tablename__ = 'users' id = column (integer, primary_key = true) name = column (string) absolute name = column (string) password = column (string) def __repr __ (self): return "& lt ; User (name = '% s', absolute name = '% s', password = '% s') & gt; "% (Self.name, self.fullname, self.password) After the problem I have typed the password = column (string) I hit twice and changed .... >> I then took everything back but then an error was thrown because the class already exists ... I am not completely sure how to fix it. How do I open that slip in the shell script and edit it (Add DF to DRR) The error thrown below: / user / giripeters / TFSQLLX / Lib / python2.7 / site-packages / sqlalchemy / ext / decla
Read more

c# - MySQL Parameterized Select Query joining tables issue -

-
I am using parameterized select questions in conjunction with my program and it works entirely, When I try to join the table Everything I have done is a small fraction: using (MySqlCommand cmd = new MySqlCommand (paramQuery) ToSql (), Connection)) /etc/ paramQuery.ToSql () Equal: "Select TableOne ID, Tableon, Department, Tablet. One by name table, Table 2 h Yes TableOnEID = @Pharmak "* / for (Int Index = 0; Index and Lt; ParamariX Parameter (.c calculation; Index ++) Cmd.Parameters.AddWithValue (paramQuery.Parameters (). ElementAt (index). , ParamQuery.Parameters (). ElementAt (index) .Value); / * ParamQuery.Parameters (). ElementAt (index) .k = "@most 0" paramQuery.Parameters (). ElementAt (index) .Value = "tableTwo.ID" * / MySqlDataReader Reader = cmd.ExecuteReader (); While (reader.Read ()) {// do stuff} } One of the tables I attempt to join is For the table, two with the same id for all. Is there something that I'm doing wrong?
Read more