i want to out put like this-
150 can be fitted in:
short
int
long
150000 can be fitted in:
int
long
1500000000 can be fitted in:
int
long
213333333333333333333333333333333333 can't be fitted anywhere.
-100000000000000 can be fitted in:
long
import java.io.;
import java.util.;
import java.text.;
import java.math.;
import java.util.regex.*;
public class Solution {
public static void main(String[] args) {
/* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
byte b;
long l;
int t, v;
int[] n;
Scanner in=new Scanner(System.in);
System.out.println("Inter the number");
v=in.nextInt();
n=new int[v];
int i=0;
while(n.hasNextInt())
{
n[i]=in.nextInt();
i++;
}
for(int k=0;k<t;k++)
{if(b<n[k])
{
System.out.println(k+"this is fit in");
System.out.println("*short");
System.out.println("*int");
System.out.println("*long");}
else if(t==n[k]){
System.out.println(n[k]+"this is fit in");
System.out.println("int");
System.out.println("long");}
else if(t<=n[k]){
System.out.println(n[k]+"this is fit in");
System.out.println("int");
System.out.println("long");}
else if((t<=n[k])&&(l==n[k])){
System.out.println(n[k]+"this is fit in");
System.out.println("long");}
else{
System.out.println(n[k]+"this not fitted any where");}}}}
A quick fix is to use an IDE like eclipse or netbeans that formats your code and makes life far easier to debug, develop in open-source and reduces the development time.
Coming to the errors: I can spot that you have missed a } at the end of the program script and I notice a syntactically wrong statement:
} else if (t <= n[k] > ) {
Please confirm to correct syntactically code and use formatting to enable fellow developers help you. Good luck!
I expect it's the fact you have no logical join (&& or ||) and value here:
else if(t<=n[k]>){
// ------------^
Also note that the type int[] has no hasNextInt method, so this line:
while(n.hasNextInt())
won't compile (as n is int[]).
There are about a half dozen other logic errors in there (using uninitialized variables, etc.), but hopefully that gets you headed the right way.
Related
When does a C++ program throw this error message:
terminate called after throwing an instance of 'std::out_of_range'
what(): basic_string::at: __n (which is 0) >= this->size() (which is 0)
Aborted (core dumped)
I was trying an algorithm problem on a website.
My function was:
int stringSimilarity(string s)
{
int size=s.size(), sum=0;
for(int i=0; i<size; i++)
{
string sub_str; int temp_sum=0;
//Creating a substring for comparison
for(int j=i, l=0; j<size, l<size-i; j++, l++)
{
sub_str.at(l)=s.at(j);
}
if(sub_str.at(0)==s.at(0))
{
temp_sum++;
int k=1;
while(sub_str.at(k)==s.at(k))
{
temp_sum++;
k++;
}
}
sum=sum+temp_sum;
}
return sum;
}
While running sample test cases, I got the error message I showed above. Can someone please tell me where am I going wrong?
EDIT:
Made the question to the point. In the original question, I had asked why my program was not compiling. But as many pointed out, it is not a compilation error, but a run-time error thrown by the program.
From documentation of std::string::at()
The function automatically checks whether pos is the valid position of
a character in the string (i.e., whether pos is less than the string
length), throwing an out_of_range exception if it is not.
In here, sub_str is an empty string (length 0), but you try to access it in the first line of your inner loop:
sub_str.at(l)=s.at(j);
One way to overcome it could be to initialize the string to have the same length of s, and edit it in place.
I have faced the same issue when I was doing code on HackerRank,So let me tell you what was my mistake:
I was taking one extra input which was not mentioned in test case so when i removed that my problem got solved.
Program was saying user will give two queries and i have to work on those queries but I was taking the query numbers too.
It was like
cin >> query;
And then i was taking 2 query q1 and q1 so during run time compiler said Abort Called and when i remove this(cin >> query;) line,My program worked fine.
This is a program for Fibonacci using Java 7 ForkJoin .
But seems like there is a dead lock.
package ForkJoin;
import java.time.LocalTime;
import java.util.concurrent.ForkJoinPool;
import java.util.concurrent.RecursiveTask;
import static java.time.temporal.ChronoUnit.MILLIS;
class Fibonacci extends RecursiveTask<Integer>{
int num;
Fibonacci(int n){
num = n;
}
#Override
protected Integer compute() {
if(num <= 1)
return num;
Fibonacci fib1 = new Fibonacci(num-1);
fib1.fork();
Fibonacci fib2 = new Fibonacci(num-2);
fib2.fork();
return fib1.join()+ fib2.join();
}
}
public class ForkJoinFibonaaciEx {
public static void main(String[] arg){
LocalTime before = LocalTime.now();
int processors = Runtime.getRuntime().availableProcessors();
System.out.println("Available core: "+processors);
ForkJoinPool pool = new ForkJoinPool(processors);
System.out.println("Inside ForkJoin for number 50: "+pool.invoke(new Fibonacci(50)));
LocalTime after = LocalTime.now();
System.out.println("Total time taken: "+MILLIS.between(before, after));
}
}
JVisualVM ---- shows there is dead lock.
Not sure what the real issue is.
Also, I have noticed codes where developers have done fork call for one portion and compute for other half of the problem.
e.g. here in this example they use fib1.fork() and fib2 they don't fork.
You can see the full example
https://github.com/headius/forkjoin.rb/blob/master/examples/recursive/Fibonacci.java
Your help is very much appreciated.
Thank you and have a great
With regards
Deenadayal Manikanta
By adding fib2.fork(); in the compute method, you are creating redundant subtask that has already been calculated before (i.e In next recursive call of fib1.fork()) . Eventually adding redundant sub-task which will take extra time. Instead you can call fib2.compute() which in turn will call fork in the recursion.
Though this is not the actual culprit for time consuming. Real problem is caused by fork.join() operation. As this operation wait for all child sub task (that might be executed by other thread) to finish.
Therefore although there are multiple threads executing at each core providing parallelism, the actual computation at leaf level is negligible compared to join operation.
Bottom line is:
We should use fork-join if below cases are true:
Problem can be solved using Divide and Conquer, creating sub-problem and recursively solve it.
Problem can't be divided upfront and is dynamic.
Also for fork-join to work effectively, we should divide the problem to only a certain level where parallel computation does more good than harm.
Try this:
class ComputeFibonacciTask extends RecursiveTask<Long> {
private int n;
public ComputeFibonacciTask(int n) {
this.n = n;
}
protected Long compute() {
if (n <= 1) {
return Long.valueOf(n);
}
else {
RecursiveTask<Long> otherTask = new ComputeFibonacciTask(n - 1);
otherTask.fork();
return new ComputeFibonacciTask(n - 2).compute() + otherTask.join();
}
}
}
The following code, which maps simple value holders to booleans, runs over 20x faster in Java than Swift 2 - XCode 7 beta3, "Fastest, Aggressive Optimizations [-Ofast]", and "Fast, Whole Module Optimizations" turned on. I can get over 280M lookups/sec in Java but only about 10M in Swift.
When I look at it in Instruments I see that most of the time is going into a pair of retain/release calls associated with the map lookup. Any suggestions on why this is happening or a workaround would be appreciated.
The structure of the code is a simplified version of my real code, which has a more complex key class and also stores other types (though Boolean is an actual case for me). Also, note that I am using a single mutable key instance for the retrieval to avoid allocating objects inside the loop and according to my tests this is faster in Swift than an immutable key.
EDIT: I have also tried switching to NSMutableDictionary but when used with Swift objects as keys it seems to be terribly slow.
EDIT2: I have tried implementing the test in objc (which wouldn't have the Optional unwrapping overhead) and it is faster but still over an order of magnitude slower than Java... I'm going to pose that example as another question to see if anyone has ideas.
EDIT3 - Answer. I have posted my conclusions and my workaround in an answer below.
public final class MyKey : Hashable {
var xi : Int = 0
init( _ xi : Int ) { set( xi ) }
final func set( xi : Int) { self.xi = xi }
public final var hashValue: Int { return xi }
}
public func == (lhs: MyKey, rhs: MyKey) -> Bool {
if ( lhs === rhs ) { return true }
return lhs.xi==rhs.xi
}
...
var map = Dictionary<MyKey,Bool>()
let range = 2500
for x in 0...range { map[ MyKey(x) ] = true }
let runs = 10
for _ in 0...runs
{
let time = Time()
let reps = 10000
let key = MyKey(0)
for _ in 0...reps {
for x in 0...range {
key.set(x)
if ( map[ key ] == nil ) { XCTAssertTrue(false) }
}
}
print("rate=\(time.rate( reps*range )) lookups/s")
}
and here is the corresponding Java code:
public class MyKey {
public int xi;
public MyKey( int xi ) { set( xi ); }
public void set( int xi) { this.xi = xi; }
#Override public int hashCode() { return xi; }
#Override
public boolean equals( Object o ) {
if ( o == this ) { return true; }
MyKey mk = (MyKey)o;
return mk.xi == this.xi;
}
}
...
Map<MyKey,Boolean> map = new HashMap<>();
int range = 2500;
for(int x=0; x<range; x++) { map.put( new MyKey(x), true ); }
int runs = 10;
for(int run=0; run<runs; run++)
{
Time time = new Time();
int reps = 10000;
MyKey buffer = new MyKey( 0 );
for (int it = 0; it < reps; it++) {
for (int x = 0; x < range; x++) {
buffer.set( x );
if ( map.get( buffer ) == null ) { Assert.assertTrue( false ); }
}
}
float rate = reps*range/time.s();
System.out.println( "rate = " + rate );
}
After much experimentation I have come to some conclusions and found a workaround (albeit somewhat extreme).
First let me say that I recognize that this kind of very fine grained data structure access within a tight loop is not representative of general performance, but it does affect my application and I'm imagining others like games and heavily numeric applications. Also let me say that I know that Swift is a moving target and I'm sure it will improve - perhaps my workaround (hacks) below will not be necessary by the time you read this. But if you are trying to do something like this today and you are looking at Instruments and seeing the majority of your application time spent in retain/release and you don't want to rewrite your entire app in objc please read on.
What I have found is that almost anything that one does in Swift that touches an object reference incurs an ARC retain/release penalty. Additionally Optional values - even optional primitives - also incur this cost. This pretty much rules out using Dictionary or NSDictionary.
Here are some things that are fast that you can include in a workaround:
a) Arrays of primitive types.
b) Arrays of final objects as long as long as the array is on the stack and not on the heap. e.g. Declare an array within the method body (but outside of your loop of course) and iteratively copy the values to it. Do not Array(array) copy it.
Putting this together you can construct a data structure based on arrays that stores e.g. Ints and then store array indexes to your objects in that data structure. Within your loop you can look up the objects by their index in the fast local array. Before you ask "couldn't the data structure store the array for me" - no, because that would incur two of the penalties I mentioned above :(
All things considered this workaround is not too bad - If you can enumerate the entities that you want to store in the Dictionary / data structure you should be able to host them in an array as described. Using the technique above I was able to exceed the Java performance by a factor of 2x in Swift in my case.
If anyone is still reading and interested at this point I will consider updating my example code and posting.
EDIT: I'd add an option: c) It is also possible to use UnsafeMutablePointer<> or Unmanaged<> in Swift to create a reference that will not be retained when passed around. I was not aware of this when I started and I would hesitate to recommend it in general because it's a hack, but I've used it in a few cases to wrap a heavily used array that was incurring a retain/release every time it was referenced.
I populate a very large array using a stxxl::VECTOR_GENERATOR<MyData>::result::bufwriter_type (something like 100M entries) which I need to sort in parallel.
I use the stxxl::sort(vector->begin(), vector->end(), cmp(), memoryAmount) method, which in theory should do what I need: sort the elements very efficiently.
However, during the execution of this method I noticed that only one processor is fully utilised, and all the other cores are quite idle (I suspect there is little activity to fetch the input, but in practice they don't do anything).
This is my question: is it possible to exploit more cores during the sorting phase, or is the parallelism used only to fetch the input asynchronously? If so, are there documents that explain how to enable it? (I looked extensively the documentation on the website, but I couldn't find anything).
Thanks very much!
EDIT
Thanks for the suggestion. I provide below some more information.
First of all I use MacOs for my experiments. What I do is that I launch the following program and I study its behaviour.
typedef struct Triple {
long t1, t2, t3;
Triple(long s, long p, long o) {
this->t1 = s;
this->t2 = p;
this->t3 = o;
}
Triple() {
t1 = t2 = t3 = 0;
}
} Triple;
const Triple minv(std::numeric_limits<long>::min(),
std::numeric_limits<long>::min(), std::numeric_limits<long>::min());
const Triple maxv(std::numeric_limits<long>::max(),
std::numeric_limits<long>::max(), std::numeric_limits<long>::max());
struct cmp: std::less<Triple> {
bool operator ()(const Triple& a, const Triple& b) const {
if (a.t1 < b.t1) {
return true;
} else if (a.t1 == b.t1) {
if (a.t2 < b.t2) {
return true;
} else if (a.t2 == b.t2) {
return a.t3 < b.t3;
}
}
return false;
}
Triple min_value() const {
return minv;
}
Triple max_value() const {
return maxv;
}
};
typedef stxxl::VECTOR_GENERATOR<Triple>::result vector_type;
int main(int argc, const char** argv) {
vector_type vector;
vector_type::bufwriter_type writer(vector);
for (int i = 0; i < 1000000000; ++i) {
if (i % 10000000 == 0)
std::cout << "Inserting element " << i << std::endl;
Triple t;
t.t1 = rand();
t.t2 = rand();
t.t3 = rand();
writer << t;
}
writer.finish();
//Sort the vector
stxxl::sort(vector.begin(), vector.end(), cmp(), 1024*1024*1024);
std::cout << vector.size() << std::endl;
}
Indeed there seems to be only one or maximum two threads working during the execution of this program. Notice that the machine has only a single disk.
Can you please confirm me whether the parallelism work on macos? If not, then I will try to use linux to see what happens. Or is perhaps because there is only one disk?
In principle what you are doing should work out-of-the-box. With everything working you should see all cores doing processing.
Since it doesnt work, we'll have to find the error, and debugging why we see no parallel speedups is still tricky business these days.
The main idea is to go from small to large examples:
what platform is this? There is no parallelism on MSVC, only on Linux/gcc.
By default STXXL builds on Linux/gcc with USE_GNU_PARALLEL. you can turn it off to see if it has an effect.
Try reproducing the example values shown in http://stxxl.sourceforge.net/tags/master/stxxl_tool.html - with and without USE_GNU_PARALLEL
See if just in memory parallel sorting scales on your processor/system.
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My group is having some discussion and strong feelings about for loop construction.
I have favored loops like:
size_t x;
for (x = 0; x < LIMIT; ++x) {
if (something) {
break;
}
...
}
// If we found what we're looking for, process it.
if (x < LIMIT) {
...
}
But others seem to prefer a Boolean flag like:
size_t x;
bool found = false;
for (x = 0; x < LIMIT && !found; ++x) {
if (something) {
found = true;
}
else {
...
}
}
// If we found what we're looking for, process it.
if (found) {
...
}
(And, where the language allows, using "for (int x = 0; ...".)
The first style has one less variable to keep track of and a simpler loop header. Albeit at the cost of "overloading" the loop control variable and (some would complain), the use of break.
The second style has clearly defined roles for the variables but a more complex loop condition and loop body (either an else, or a continue after found is set, or a "if (!found)" in the balance of the loop).
I think that the first style wins on code complexity. I'm looking for opinions from a broader audience. Pointers to actual research on which is easier to read and maintain would be even better. "It doesn't matter, take it out of your standard" is a fine answer, too.
OTOH, this may be the wrong question. I'm beginning to think that the right rule is "if you have to break out of a for, it's really a while."
bool found = false;
x = 0;
while (!found && x < LIMIT) {
if (something) {
found = true;
...handle the thing...
}
else {
...
}
++x;
}
Does what the first two examples do but in fewer lines. It does divide the initialization, test, and increment of x across three lines, though.
I'd actually dare to suggest consideration of GOTO to break out of loops in such cases:
for (size_t x = 0; x < LIMIT && !found; ++x) {
if (something)
goto found;
else {
...
}
}
// not found
...
return;
found:
...
return;
I consider this form to be both succint and readable. It may do some good in many simple cases (say, when there is no common processing in this function, in both found/unfound cases).
And about the general frowning goto receives, I find it to be a common misinterpretation of Dijkstra's original claims: his arguments favoured structured loop clauses, as for or while, over a primitive loop-via-goto, that still had a lot of presence circa 1968. Even the almighty Knuth eventualy says -
The new morality that I propose may
perhaps be stated thus: "Certain go to
statements which arise in connection with
well-understood transformations are acceptable, provided that the program documentation explains what the transformation was."
Others here occasionaly think the same.
While I disagree that an extra else really makes the 2nd more complicated, I think it's primarily a matter of aesthetics and keeping to your standard.
Personally, I have a probably irrational dislike of breaks and continues, so I'm MUCH more likely to use the found variable.
Also, note that you CAN add the found variable to the 1st implementation and do
if(something)
{
found = true;
break;
}
if you want to avoid the variable overloading problem at the expense of the extra variable, but still want the simple loop terminator...
The former example duplicates the x < LIMIT condition, whereas the latter doesn't.
With the former, if you want to change that condition, you have to remember to do it in two places.
I would prefer a different one altogether:
for (int x = 0; x < LIMIT; ++x) {
if (something) {
// If we found what we're looking for, process it.
...
break;
}
...
}
It seems you have not any trouble you mention about one or the other... ;-)
no duplication of condition, or readability problem
no additional variable
I don't have any references to hand (-1! -1!), but I seem to recall that having multiple exit points (from a function, from a loop) has been shown to cause issues with maintainability (I used to know someone who wrote code for the UK military and it was Verboten to do so). But more importantly, as RichieHindle points out, having a duplicate condition is a Bad Thing, it cries out for introducing bugs by changing one and not the other.
If you weren't using the condition later, I wouldn't be bothered either way. Since you are, the second is the way to go.
This sort of argument has been fought out here before (probably many times) such as in this question.
There are those that will argue that purity of code is all-important and they'll complain bitterly that your first option doesn't have identical post-conditions for all cases.
What I would answer is "Twaddle!". I'm a pragmatist, not a purist. I'm as against too much spaghetti code as much as the next engineer but some of the hideous terminating conditions I've seen in for loops are far worse than using a couple of breaks within your loop.
I will always go for readability of code over "purity" simply because I have to maintain it.
This looks like a place for a while loop. For loops are Syntactic Sugar on top of a While loop anyway. The general rule is that if you have to break out of a For loop, then use a While loop instead.
package com.company;
import java.io.*;
import java.util.Scanner;
public class Main {
// "line.separator" is a system property that is a platform independent and it is one way
// of getting a newline from your environment.
private static String NEWLINE = System.getProperty("line.separator");
public static void main(String[] args) {
// write your code here
boolean itsdone = false;
String userInputFileName;
String FirstName = null;
String LastName = null;
String user_junk;
String userOutputFileName;
String outString;
int Age = -1;
int rint = 0;
int myMAX = 100;
int MyArr2[] = new int[myMAX];
int itemCount = 0;
double average = 0;
double total = 0;
boolean ageDone = false;
Scanner inScan = new Scanner(System.in);
System.out.println("Enter First Name");
FirstName = inScan.next();
System.out.println("Enter Last Name");
LastName = inScan.next();
ageDone = false;
while (!ageDone) {
System.out.println("Enter Your Age");
if (inScan.hasNextInt()) {
Age = inScan.nextInt();
System.out.println(FirstName + " " + LastName + " " + "is " + Age + " Years old");
ageDone = true;
} else {
System.out.println("Your Age Needs to Have an Integer Value... Enter an Integer Value");
user_junk = inScan.next();
ageDone = false;
}
}
try {
File outputFile = new File("firstOutFile.txt");
if (outputFile.createNewFile()){
System.out.println("firstOutFile.txt was created"); // if file was created
}
else {
System.out.println("firstOutFile.txt existed and is being overwritten."); // if file had already existed
}
// --------------------------------
// If the file creation of access permissions to write into it
// are incorrect the program throws an exception
//
if ((outputFile.isFile()|| outputFile.canWrite())){
BufferedWriter fileOut = new BufferedWriter(new FileWriter(outputFile));
fileOut.write("==================================================================");
fileOut.write(NEWLINE + NEWLINE +" You Information is..." + NEWLINE + NEWLINE);
fileOut.write(NEWLINE + FirstName + " " + LastName + " " + Age + NEWLINE);
fileOut.write("==================================================================");
fileOut.close();
}
else {
throw new IOException();
}
} // end of try
catch (IOException e) { // in case for some reason the output file could not be created
System.err.format("IOException: %s%n", e);
e.printStackTrace();
}
} // end main method
}