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Basic for loop in java and data storage

I am very new to coding and I have a simple question. I want to input day, month and year inside a for loop and after inputting it I want to display all the inputted values on the same time. how to do it.kindly help me.
i have attached the code below.
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
int n = in.nextInt();
for(int i=0;i<n;i++) {
int day = in.nextInt();
String month = in.next();
int year = in.nextInt();
}}
//need to display the entire content from the for loop
//suppose if the n value is 3
//i will be giving 3 inputs
//10 jan 1998
//11 nov 2000
//12 dec 1995
//i want to print all at the same time
Kindly help me with it.

If I understood your question correctly and you just want to print your inputs, just add the following to the loop:
System.out.println(String.format("%d %s %d", day, month, year));
or otherwise, but not as pretty (at least in my opinion):
System.out.println(day + " " + day + " " + month + " " + year);
EDIT
As indicated, you want to print them all at the same time. To do so, you can just save them all in a list or an array for example like the following:
Before the loop:
String[] dates = new String[n];
In the loop:
dates[i] = String.format("%d %s %d", day, month, year);
And then go ahead and insert another loop to print the content of the array:
for(String date: dates){
System.out.println(dates[i]);
}

From what I have gathered, you are looking to set a number on how many dates you'd like the user to enter, take in that number of dates and then print out the dates after the user input.
Here is some basic code that will do that for you
public static void main(String args[]) {
Scanner sc = new Scanner(System.in);
int numOfInputs = 3; //How many separate dates you would like to enter
int day[] = new int[numOfInputs]; //declaring an integer array day and setting the array size to the value of numOfInputs
String month[] = new String[numOfInputs]; //declaring a string array month and setting the array size to the value of numOfInputs
int year[] = new int[numOfInputs]; //declaring an integer array year and setting the array size to the value of numOfInputs
//get inputs
for(int i=0;i<numOfInputs;i++) {
System.out.println("Please enter a day");
day[i] = sc.nextInt();
System.out.println("Please enter a month");
month[i] = sc.next();
System.out.println("Please enter a year");
year[i] = sc.nextInt();
}
//print content
for(int i=0;i<numOfInputs;i++) {
System.out.println(day[i] + " " + month[i] + " " + year[i]);
}
//close scanner
sc.close();
}
Let me know if this doesn't answer your question or if you need any clarification.

Java: Loop that has a user enter integers not totaling the entries correctly

I need to write a program that asks for integers and loops until the input is a negative integer, when the program will then end. Additionally, the loop needs to count the total number of positive integer entries and add all of the entries together. The count portion of the code seems to work fine, but my approach to getting the sum of all entries is NOT working.
What I have tried in my code is to put total=total+input at the end of my loop, but this isn't giving the correct sum when tested.
Additionally, my type safe block only works for the first entry; if I enter a letter after an integer, it crashes the program. Shouldn't that loop back to the type safe block at the beginning of each entry?
I pasted a copy of my output at the bottom.
Any help would be appreciated.
int count = 0;
int total = 0;
Scanner scan = new Scanner(System.in);
System.out.print( "Enter an integer, negative to quit: " );
while(!scan.hasNextInt())
{
scan.nextLine();
System.out.println( "That is not an integer." );
System.out.println( "Please enter an integer." );
}
int input = scan.nextInt();
while (input >= 0)
{
System.out.print( "Next integer: " );
input = scan.nextInt();
count++;
total = total + input;
}
System.out.println( "Count: " + count );
System.out.println( "Total: " + total );
When I run my code, I get the following output:
run:
Enter an integer, negative to quit: h
That is not an integer.
Please enter an integer:
1
Next integer: 2
Next integer: 3
Next integer: -1
Count: 3
Total: 4
BUILD SUCCESSFUL (total time: 10 seconds)

Swap the order of operations. First sum and count, then get a new input:
while (input >= 0) {
total = total + input;
count++;
System.out.print("Next integer: ");
input = scan.nextInt();
}
Your current code discards the first input 1 and starts summing and counting with the second input 2.

You need to check on each iteration if the next entry is an integer or not. Aditionally you need to sum the initial integer before you ask for the next one:
int input = 0;
int count = 0;
int total = 0;
do{
System.out.print("Enter an Integer: ");
total += input;
if(!scan.hasNextInt()) {
scan.nextLine();
System.out.println( "That is not an integer." );
input = 0;
} else {
input = scan.nextInt();
count++;
}
} while(input >= 0);
System.out.println("Count: " + (count - 1));
System.out.println("Total: " + total);

Difficulty Adding Values and Array Lengths [duplicate]

This question already has answers here:
What causes a java.lang.ArrayIndexOutOfBoundsException and how do I prevent it?
(26 answers)
Closed 3 years ago.
I'm trying to write some code to calculate an on base percentage. The program gathers the players name, year he has played on the team (size of array) and the year he started. Once I begin the array and start the information, if the user entered two years, I receive an error right at the second value because of the arrays length. How do I get around this issue? Any help is appreciated. Thank you.
This is the error I receive: "java.lang.ArrayIndexOutOfBoundsException: 2"
I've tried creating variables for each item, adding and dividing to get the on base percentage. Once I do that, I can't seem to figure out how to print that out for each year. For example "Year 1985: -OBP-, Year 1986: -OBP-"
import java.util.Scanner;
public class RyanBaseballOBPArray
{
public static void main(String[] args)
{
int numYears;
double [] years;
String name;
int startYear;
double oBP;
Scanner keyboard = new Scanner(System.in);
System.out.print("Enter name of baseball player: ");
name = keyboard.nextLine();
System.out.print("Enter the number of years " + name +" has been playing: ");
numYears = keyboard.nextInt();
years = new double[numYears];
System.out.print("Enter " +name +" first year on the team: ");
startYear = keyboard.nextInt();
for (int index = 0; index < years.length; index++)
{
System.out.print("For Year " + (index +1 ) + "\nEnter number of hits: ");
years[1] = keyboard.nextInt();
System.out.print("For Year " + (index +1) + "\nEnter number of walks: ");
years[2] = keyboard.nextInt();
System.out.print("For Year" + (index +1) + "\nEnter the number of times player"
+ "has been hit by a pitch:");
years[3] = keyboard.nextInt();
System.out.print("For Year" + (index +1) + "\nEnter the number of at bats:");
years[4] = keyboard.nextInt();
System.out.print("For Year" + (index +1) + "\nEnter the number of sacrafice flies"
+ "that year: ");
years[5] = keyboard.nextInt();
years[0] = (years[1] + years[2] + years[3]) / years[4] + years[2] + years[3] + years[5];
}
printOnBasePercentage(name, startYear, years);
}
public static void printOnBasePercentage(String name, int startYear, double []years){
System.out.println(name + "'s On Base Percentage");
System.out.println(years[0]);
}
}

I believe your issue stems from the fact you have hard-coded array access to the years array whose length is defined by keyboard input.
years[5] = keyboard.nextInt();
Thus if someone only plays for 3 years there are only 3 elements in the year array, and you are trying to access the 6th giving you an out of bounds exception.

Listing multiples of user-inputted numbers

The task is to "Write a program that displays a user-indicated number of multiples for an integer entered by the user."
I suppose I do not need a completely direct answer (although I do want to know the methods/formula to use), as I want to use this as a learning experience in order to do and learn from the task myself. I really want to know about the process and which methods to use, along with finding a formula. :||
I'm really not sure how to write a code that displays a user-inputted number of a user-inputted integer. The hardest part seems to be writing the loop formula. Not sure where to start.
So far, I have:
import java.util.Scanner;
public class MultipleLooping
{
public static void main(String[] args)
{
Scanner keyboard = new Scanner(System.in);
\\just stuff to base my code off of
int integer;
int numberMultiples;
System.out.println("Enter an integer: ");
integer = keyboard.nextInt();
System.out.println("How many multiples of " + integer + " would you like to know?");
numberMultiples = keyboard.nextInt();
System.out.println("Listing the first " + numberMultiples + " multiples of " + integer + ": ");
\\pretty much everything from here on out.. I'm not sure what to really do.
int n = integer;
int result = (integer * (numberMultiples));
while (result > 0){}
System.out.print(result);
}
} \\at the moment this code doesn't seem to have any running errors
I'm really not sure how to write a code that displays a user-inputted number of a user-inputted integer. The hardest part seems to be writing the loop formula. Not sure where to start.
NEW QUESTION
I need to loop my program as well. (By asking a question to the user first.) Mines isn't working, as it just keeps looping only the integer loop and doesn't let me type yes/no.
import java.util.Scanner;
public class MultipleLoops
{
public static void main(String[] args)
{
Scanner keyboard = new Scanner(System.in);
int integer, numberMultiples;
String repeat = "yes";
while (repeat != "no")
{
System.out.println("Enter an integer: ");
integer = keyboard.nextInt();
System.out.println("How many multiples of " + integer + " would you like to know?");
numberMultiples = keyboard.nextInt();
System.out.println("Listing the first " + numberMultiples + " multiples of " + integer + ": ");
for (int i=1; i<=numberMultiples; i++){
System.out.println(integer + " * " + i + " = " + i*integer );
}
System.out.println("Would you like to do this again? Enter yes or no: ");
repeat = keyboard.nextLine();
}
}
}

Ok so you need to understand the problem first to know how to solve it
x = First input
n = Second input
you need to calculate n multiple of x
example with x = 3 and n = 10
To calculate 10 multiple of 3 we need to do :
1st multiple = x*1
2nd multiple = x*2
3rd multiple = x*3
...
n multiple = x*n
you can notice that these operations can be replaced by one for loop (notice first and last character of every line, it can be index of your loop )
Back to java :)
for (int i=1; i<=numberMultiples; i++){
System.out.println("Listing multiple N# " + i + " = "+ i*integer );
}
Replace your code with the following and try this code :
import java.util.Scanner;
public class MultipleLooping{
public static void main(String[] args){
Scanner keyboard = new Scanner(System.in);
int integer,numberMultiples;
System.out.println("Enter an integer: ");
integer = keyboard.nextInt();
System.out.println("How many multiples of " + integer + " would you like to know?");
numberMultiples = keyboard.nextInt();
for (int i=1; i<=numberMultiples; i++){
System.out.println("Listing multiple N# " + i + " = "+ i*integer );
}
}
}
Enter an integer:
3
How many multiples of 3 would you like to know?
7
Listing multiple N# 1 = 3
Listing multiple N# 2 = 6
Listing multiple N# 3 = 9
Listing multiple N# 4 = 12
Listing multiple N# 5 = 15
Listing multiple N# 6 = 18
Listing multiple N# 7 = 21

Do you want like this ? Below is the code
package com.ge.cbm;
import java.util.Scanner;
public class MultipleLooping
{
public static void main(String[] args)
{
Scanner keyboard = new Scanner(System.in);
//just stuff to base my code off of
int integer;
int firstEntered;
int numberMultiples;
System.out.println("Enter an integer: ");
integer = keyboard.nextInt();
firstEntered = integer;
System.out.println("How many multiples of " + integer + " would you like to know?");
numberMultiples = keyboard.nextInt();
System.out.println("Listing the first " + numberMultiples + " multiples of " + integer + ": ");
//pretty much everything from here on out.. I'm not sure what to really do.
for (int i=0;i<numberMultiples;i++){
integer=integer*firstEntered;
System.out.println(integer);
}
}
}
Output:
Enter an integer:
3
How many multiples of 3 would you like to know?
7
Listing the first 7 multiples of 3:
9
27
81
243
729
2187
6561

this should work
while(repeat.equals("yes"))
{
System.out.println("Enter an integer: ");
integer = keyboard.nextInt();
System.out.println("How many multiples of " + integer + " would you like to know?");
numberMultiples = keyboard.nextInt();
System.out.println("Listing the first " + numberMultiples + " multiples of " + integer + ": ");
for (int i=1; i<=numberMultiples; i++)
{
System.out.println(integer + " * " + i + " = " + i*integer );
}
System.out.println("Would you like to do this again? Enter yes or no: ");
repeat = keyboard.nextLine();
repeat = keyboard.nextLine();
}

Need help declaring a variable within a for loop (Java)

I'm currently working on a program and ran into an error while trying to execute a for loop. I want to declare a variable in the for loop, then break once that variable obtains a certain value, but it returns the error "cannot be resolved to a variable."
Here's my code
int i = -1;
for (; i == -1; i = index)
{
Scanner scan = new Scanner(System.in);
System.out.println("Please enter your first and last name");
String name = scan.nextLine();
System.out.println("Please enter the cost of your car,"
+ "\nthe down payment, annual interest rate,"
+ "\nand the number of years the car is being"
+ "\nfinanced, in that order.");
DecimalFormat usd = new DecimalFormat("'$'0.00");
double cost = scan.nextDouble();
double rate = scan.nextDouble();
int years = scan.nextInt();
System.out.println(name + ","
+ "\nyour car costs " + usd.format(cost) + ","
+ "\nwith an interest rate of " + usd.format(rate) + ","
+ "\nand will be financed annually for " + years + " years."
+ "\nIs this correct?");
String input = scan.nextLine();
int index = (input.indexOf('y'));
}
I want to run the output segement of my program until the user inputs yes, then the loop breaks.

The variable index's scope is local to the block of the for loop, but not the for loop itself, so you can't say i = index in your for loop.
You don't need index anyway. Do this:
for (; i == -1;)
or even
while (i == -1)
and at the end...
i = (input.indexOf('y'));
}
Incidentally, I'm not sure you want input.indexOf('y'); an input of "blatherskyte" will trigger this logic, not just "yes", because there's a y in the input.

Instead of using a for loop, you can do-while(it suits much better for this scenario.
boolean exitLoop= true;
do
{
//your code here
exitLoop= input.equalsIgnoreCase("y");
} while(exitLoop);

for indefinite loop, i would prefer while.
boolean isYes = false;
while (!isYes){
Scanner scan = new Scanner(System.in);
System.out.println("Please enter your first and last name");
String name = scan.nextLine();
System.out.println("Please enter the cost of your car,"
+ "\nthe down payment, annual interest rate,"
+ "\nand the number of years the car is being"
+ "\nfinanced, in that order.");
DecimalFormat usd = new DecimalFormat("'$'0.00");
double cost = scan.nextDouble();
double rate = scan.nextDouble();
int years = scan.nextInt();
System.out.println(name + ","
+ "\nyour car costs " + usd.format(cost) + ","
+ "\nwith an interest rate of " + usd.format(rate) + ","
+ "\nand will be financed annually for " + years + " years."
+ "\nIs this correct?");
String input = scan.nextLine();
isYes = input.equalsIgnoreCase("yes");
}

You cannot do this. If the variable is declared inside of the loop, then it is re-created every run. In order to be part of the condition for exiting the loop, it must be declared outside of it.
Alternatively, you could use the break keyworkd to end the loop:
// Should we exit?
if(input.indexOf('y') != -1)
break;

Here you want to use a while loop. Usually you can decide which loop to use by saying your logic out loud to yourself, While this variable is(not) (value) do this.
For your problem, initialize the variable outside of the loop, and then set the value inside.
String userInput = null;
while(!userInput.equals("exit"){
System.out.println("Type exit to quit");
userInput = scan.nextLine();
}