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C rand always the same

WebFeb 6, 2016 · Objective of code: The code uses omp to simply run a piece of code for 3 threads. Each thread has to print 3 random values using the rand () function. So, a total of 9 outputs would come. Thread 0 is the main thread/ the main program's run flow. Thread 1 and Thread 2 are the fellow new threads created at the start of code for the threads. WebNov 6, 2024 · Yes, given the same environment for the program. From the C standard §7.20.2.2/2, The srand function uses the argument as a seed for a new sequence of pseudo-random numbers to be returned by subsequent calls to rand. If srand is then called with the same seed value, the sequence of pseudo-random numbers shall be repeated.

c++ - rand() gives still the same value - Stack Overflow

WebWhen I'm using rand () it gives me the same value several times in a row. The smaller number range, the bigger the problem is. For example for (i=0; i<10; i++) { x = rand () % 20 + 1; cout << x << ", "; } Will give me 1, 1, 1, 2, 1, 1, 1, 1, 14, - … WebMay 18, 2012 · Each possible seed corresponds to a specific set of pseudorandom numbers, which are always the same when that seed is used. Since you're going based off of seconds, you're not giving it time to change. Therefore, you're getting the first number of the same set of numbers each time. budget direct ad actors 2021 https://deltasl.com

c++ - rand() returns the same number each time the program is …

WebDec 7, 2024 · rand () or std::rand () never generates true random number. It generates pseudo-random numbers. This is because computers are unable to generate truly random numbers itself, it requires assistance. Let's say you pressed a key exactly 2.054 seconds after the previous keypress. This is truly a random number. WebApr 14, 2024 · 93 views, 5 likes, 9 loves, 47 comments, 30 shares, Facebook Watch Videos from Radio Eersteriver: The House Edition Show with DJ JAYO SA... WebFeb 15, 2024 · You haven't seeded the C random number generator by calling ONCE srand (); Add the following line before you enter your while loop: srand (time (NULL)); You will also need to include the header. I would suggest you get away from using the C pseudo random number generator and look into the C++ library . crick in head

How does rand() work in C? - Stack Overflow

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C rand always the same

c++ - Rand () command generates the same numbers every time

WebFeb 22, 2015 · To initialize the random number generator, you need to call srand () with a seed. You only need to initialize it once. You will get the same sequence of numbers with the same seed, so normally, people use the current time as seed as that is pretty much guaranteed to change between program executions: srand (time (0)); Share Improve this … WebNov 23, 2009 · The easiest method is to use time () For example. srand (time (NULL)); rand ();//now returns a random number. The reason is that the random numbers provided by rand () (or any other algorithm based function) aren't random. The rand function just takes its current numerical state, applies a transformation, saves the result of the transformation ...

C rand always the same

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WebOct 13, 2011 · The rand () function is specifically required to produce the same sequence of numbers when seeded with a given seed (by calling srand () ); each possible seed value specifies a sequence. And if you never call srand (), you get the same sequence you would have gotten by calling srand (1) before any call to rand (). WebThis is really weird, and I cannot see why this is happening. In the foreach cycle, I am iterating through a class A collection, and for each class, I call the Count() method, where r1 and r2 numbers are generated from range [-1,1]. The problem is that Random.Next returns the same "random" numbers for each instance. When the results for the first instance …

WebJul 20, 2015 · The versions of rand () and srand () in the Linux C Library use the same random number generator as random () and srandom (), so the lower-order bits should be as random as the higher-order bits.

WebDec 18, 2014 · 2 Answers. #include #include #include int main (void) { int a; srand ( time (NULL) ); a = rand (); printf ("%d",a); return 0; } You need to seed the generator. This is expected. The reason is for repeatability of results. WebJan 7, 2015 · The answer is simple. Change the seed before you generate random. Example: I want to generate random number between 1 to 10 Random rnd = new Random (DateTime.Now.Second); int random_number = rnd.Next (10); Put it inside a loop and run it three times. It will give out random numbers below 10. Share Improve this answer Follow

WebJun 8, 2016 · Every time you call rand () it takes the seed and/or the last random number (s) generated (the C standard doesn't specify the algorithm used, though C++11 has facilities for specifying some popular algorithms), runs a mathematical operation on those numbers, and returns the result.

WebOct 14, 2024 · srand (1); cout << rand () << ' '; cout << rand () << ' '; cout << rand () << ' '; It will produce 52 2462 77 (for example; just made-up numbers). The solution is just to not call srand () within a loop. Call it at the beginning of your program, before any loop happens. Otherwise you'll keep resetting the state of the sequence. budget direct car claim onlineWebMay 19, 2014 · MPI: rand () gives the same constant numbers across all processes in every run. I would like to ask a question about rand () in the context of (Open)MPI. We were given an implementation task in our parallel programming course - create an MPI application in which all participant processes chose one leader (randomly - they have to "vote"). budget direct car and home insuranceWebMar 20, 2015 · The rand () function returns a pseudo-random integer in the range 0 to RAND_MAX inclusive pseudo-random means that given the same input, called a seed, it will give the same output. This is actually quite useful when you're trying to debug a problem since the same "random" values will be returned, letting you reproduce the problem. budget direct business car insuranceWebFeb 15, 2024 · I would suggest you get away from using the C pseudo random number generator and look into the C++ library . The C standard recommends not … budget direct cancellation feeWebSep 5, 2024 · 2. If random numbers are generated with rand () without first calling srand (), your program will create the same sequence of numbers each time it runs. The srand () function sets the starting point for producing a series of pseudo-random integers. If srand () is not called, the rand () seed is set as if srand (1) so, set srand (time (0)); at ... budget direct car insurance callWebOct 28, 2015 · The srand () function sets its argument as the seed for a new sequence of pseudo-random integers to be returned by rand (). These sequences are repeatable by calling srand () with the same seed value. If no seed value is provided, the rand () function is automatically seeded with a value of 1. budget direct business insuranceWebNumbers generated by rand () are not random, they are *pseudo*random: given the same seed, it will always return the same sequence. By default, I believe the initial seed is zero (however, it is for sure always the same between program runs - so without seeding you'll always get the same apparently random sequence every time). Share budget direct car insurance claim form