if you cant eval 1M of primes, it literally no purpose to talk about performance anyway

I'll try to upgrade it so that it can do that

how it is going?

I'm trying to use gdb to see if I can check the execution time between two breakpoints, but I think I can't do that. I tried to use reppl.it but it does not compile in debug mode and anyway, even if I do that manually, I still have to use gdb as the debugger... so same problem

I don't know why but if n > 520184 it breaks

Maybe I know why...

Maybe I know why...

why?

why?

The debugger tells me that the problem is in line 31, where I write primes[counter] = i; I use counter to initialize dynamically the array of primes using a maths theorem which says that primes between 1 and n are not more than n/log(n), but since the problem is signaled here, maybe the program tries to access a non-initialised space, mabye because the program finds somehow counter + 1 primes (don't know how), so that everything brakes

If that is true... and I really don't know... I should be able to fix it really easely

If that is true... and I really don't know... I should be able to fix it really easely

can you preallcate 1M array of int64 for primes?

you mean, not dynamically?

you mean, not dynamically?

using calloc, not malloc

ok

It finds 78498 when I just allocate 72383 doublewords. Either my algorithm doesn't work or I haven't understood the formula n/log(n) to understand how many primes are there between 1 and n

Now I'm tired, so I'll see tomorrow how to solve this.

using calloc, not malloc

I changed, but the only difference I can see in in the syntax

It finds 78498 when I just allocate 72383 doublewords. Either my algorithm doesn't work or I haven't understood the formula n/log(n) to understand how many primes are there between 1 and n

this formula is not a number of prime numbers. you have prime numbers count - it is a 1000000

what difficulties to calculate 1000000 prime numbers?

allocate 1000000 array elements

Yeah bro, but I don't wanna allocate so much to store the first 3 primes... I wanted to do something dynamically. I understood that I used the wrong formula tu approximate whe number of primes between 1 and n, that's it

allocate 1000000 array elements

now it works, I changed formula

it works also for numbers up to 10^9, but it takes a lot of time

30 seconds just to elaborate

that is slow, that is slow as hell

that is slow, that is slow as hell

ok, good. cache primes, do not use i, i+1, i+2, use 6*i-1,6*i+1, cause 6i+2 == 0 mod 3, 6i + 3 == 0 mod 2, 6i + 4 == 0 mod 2, and 6i + 5 == 6i -1 mod n

ok, good. cache primes, do not use i, i+1, i+2, use 6*i-1,6*i+1, cause 6i+2 == 0 mod 3, 6i + 3 == 0 mod 2, 6i + 4 == 0 mod 2, and 6i + 5 == 6i -1 mod n

okk, tomorrow I'll try to do like that

Someone Know How can create an float vector with push_back?

Someone Know How can create an float vector with push_back?

How to create float vector and then use push back or what are you asking?

I'm trying to pushback floats values in a vector (like [0.01,0.02..]), but when I print the components of the vector are wrong

I used a for loop

I want create an vector [0.01,0.02....10]

How can I do?

Why you're working on a site and not on Microsoft Visual Stodio?

And please delete before you'll get warn

I want create an vector [0.01,0.02....10]

e.g. double StepSize = 0.01; double Min = 0 + StepSize; double Max = 10; std::vector<double> V; for (double Current = Min; Current <= Max; Current += StepSize) { V.push_back(Current); }

Hello friends, how are you? I have an application code that I want to adjust to make the latest version of the application work. There is a jailbreak. Does anyone know what ..?

One thing I can say is that you're assigning 0.01, 0.02 etc in index 0.01 etc. which is a float(☉ ｡☉)!

Xqq

#ot

/warn screen photo

i += 1 in the the loop statement t[i] = t[i-1] + dt in the loop score

Add a condition for i = 0

e.g. double StepSize = 0.01; double Min = 0 + StepSize; double Max = 10; std::vector<double> V; for (double Current = Min; Current <= Max; Current += StepSize) { V.push_back(Current); }

If you don't understand this

And please delete before you'll get warn

You tried, Swarley 😂

Hii

Hi

Hii

You tried, Swarley 😂

😅

Hey again... I did a stupid thing and I don't know how to make it short.... void countArray(int arr[][COLS], int cols, int rows) { for (int i = 0; i < rows; i++) { for (int j = 0; j < cols; j++) { arr[0][2] = arr[0][0] + arr[0][1]; arr[1][2] = arr[1][0] + arr[1][1]; arr[2][2] = arr[2][0] + arr[2][1]; arr[3][2] = arr[3][0] + arr[3][1]; printf("%d ", arr[i][j]); } printf("\n"); } } how do I make it without printing every single cell? or what shell I ask Google exactly? lol..

Didn't understand

Didn't understand

What statement is printing things to the console according to you?

Didn't understand

Just remove the print statement if you don't want to print. It's obvious

What statement is printing things to the console according to you?

printf?

printf?

Yes. Looks like this is your first time looking at a piece of code.

Yes. Looks like this is your first time looking at a piece of code.

If you don't understand my question don't answer

printf?

Yes, remove or move it, if you don't want it to print it. Also other four statements inside for loop doesn't make sense

If you don't understand my question don't answer

Lol

Yes, remove or move it, if you don't want it to print it. Also other four statements inside for loop doesn't make sense

I'm asking how to print the long code I did short in what statement because I'm doing it wrong, I want a short way to write the cell plus cell = 3thcell

I'm asking how to print the long code I did short in what statement because I'm doing it wrong, I want a short way to write the cell plus cell = 3thcell

What do you mean by long code?

What do you mean by long code?

I did every cell plus the other cell = the last I didn't get how to do it not in that way, because if I'll have millions of cells that won't be the way..

I'm asking how to print the long code I did short in what statement because I'm doing it wrong, I want a short way to write the cell plus cell = 3thcell

Also you might want to explain what operation you want to do

I did every cell plus the other cell = the last I didn't get how to do it not in that way, because if I'll have millions of cells that won't be the way..

Use i and j

In place of numbers

Use i and j

On the first?

On the first?

You have have to understand what will be the value of i and j as the loop increments and use their values in place of the numbers according to what you want.

On the first?

You might want to think in terms of coordinates.

You have have to understand what will be the value of i and j as the loop increments and use their values in place of the numbers according to what you want.

I'm trying to understand logecly how to make it with out writing every single cells.. (I'm 2d array begginer, just started with the 2d yesterday)

I'm trying to understand logecly how to make it with out writing every single cells.. (I'm 2d array begginer, just started with the 2d yesterday)

You put it inside a for loop like you are doing, just make sure your statement are in terms of i and j

I'm trying to understand logecly how to make it with out writing every single cells.. (I'm 2d array begginer, just started with the 2d yesterday)

According to your code with every increment of the variable i, j increments cols times.

So make logic in your head with where you should use i and where j

Here, might want to read on mathematical induction to recognize patterns, if it is very difficult to find a pattern to loop with. https://youtu.be/GvbrtnEYRpY

Hello guys please help me can i use code block for programming sockets in C++ ? . I tried to search it via YouTube i didn't find answer

Hello guys please help me can i use code block for programming sockets in C++ ? . I tried to search it via YouTube i didn't find answer

You can use any ide.

You can use any ide.

Thank u so much i will try 😀😀

Would this be a... good way to implement a basic plugin audio IO? Plugin: https://gist.github.com/46e96a9b56cc1f876f6355e7cba1a992 Engine: https://gist.github.com/56c476a9b0b0ae34934bfb1277e1cded

Guyes pls help me i found good algorytm for printing lines "Bresenham's line algorithm" but i am lost how implement it in 2D array can please someone help me? Thanks

Can anyone please tell me.. How to store a character in a variable whose ascii code I already have in another variable..

Can anyone please tell me.. How to store a character in a variable whose ascii code I already have in another variable..

you already store it. if you want to printf it use %c or cast to char for cout

you already store it. if you want to printf it use %c or cast to char for cout

Can you please elaborate the phrase " cast to char for cout " ..i am not much learned in C so i'm not familiar with this phrase..

what are you trying to achieve? you already store this character. there is no difference between char c = 'A' vs char c = 65(ascii one byte encoding)