C++ :: Random Generator Generates Same Numbers Each Time?
Apr 24, 2014
The user thinks of a number from 0 to 100 and the program tries to guess it. The problem is, I'm new to random numbers and use a function to generate them that isn't my own. It generates the same numbers each time the program runs, here are screen shots:
Run 1: [URL] .....
Run 2: [URL] .....
I read something about seeding or something, if I need it, must don't give me the answer. If you have the liberty of time explain more to me about the random business.
Here is my code:
#include <iostream>
#include <cstdlib>
#include <iomanip>
#include <unistd.h>
#include <string>
#include <ctime>
using namespace std;
int rand_lim(int limit) {
This is my program i have to choose for random number between 1-25 and display them the program works perfectly just that every time i run its always the same numbers.
#include <iostream> #include <cstdlib> // include library to use rand using namespace std; int main(){ int winner1; // declare variables int winner2;
so the program will create a random value for the inflow. The idea is that the internal for loop will continue to run until the fill_level of the reservoir, which starts at 0, hits the capacity. The process of simulating how many years (each iteration of the internal for loop representing a year) is to be repeated 10 times by the parent for loop of the water_level simulation for loop.
The problem is that the random number that is supposed to created are the same number. THey are different every time I run it, but they are the same every time the loops repeat to make a new simulation.
I need to write a C function that generates a random character array (i.e. string) of uppercase letters - getchar and putchar are the only IO functions that I can use. Below is what I have already - I am iterating for as many times as I am required to, and am modulating rand() by 25, (total letters in the alphabet). I'm trying to see how to get the random letter from the % 25, and also how to do this without toupper() [not sure if I can use that function].
void getRandomStr()){ char str[40]; for (int i = 0; i < 40; i++){ char c = rand() % 25); str[i] = toupper(c); }}
Below is a program that generates random Addition for Subtraction problems depending on the user's choice. The user is prompted to input an answer and then it keeps your score. If you want to quit you just press zero.
Code: #include <iostream> #include <stdio.h> #include <stdlib.h> #include <time.h> #include <iomanip> #include <string> using namespace std; int menu(); bool addition(int &reward); // function to return truth values
I'm trying to use a random response generator. I found a ton of information on this site, and I'm running a (very simple) program that is using 5 responses. My issue is, that every time I run the program (debug in visual express), it generates the same responses, in the same order, every time.
#include <iostream> #include <string> using namespace std; int main() { string mystr; cout << "Hello. How are you today?
Write a program that generates an array of 20 random numbers between 1 and 100. Use a loop to output the numbers on the screen with a field width of 4 characters. Write code that will reverse the numbers in the array and then output the numbers to the screen with a copy of the same output loop used with the original numbers.
The program has two array of character. One of them has size 26 and is initialized with the alphabet a to z. A random number generator generates two numbers and these two numbers are used to index into this array of alphabets. The second array is used to hold the indexed alphabets. For example, the first row is the value held in the second array and the second row are the two generated numbers.
b g c z k e <- letter index by generate number n1=1 n2=6 n1=2 n2=25 n1=10 … … … … n2=4 <- generated n1 & n2
Please see illustration below for clarification on the above question.
Element a b c ……… x y z Index 0 1 2 ……… 23 24 25
Array2 Element a b c ……… x y z Index 0 1 2 ……… 23 24 25
Final state after program execution
Array1 Element a b c ……… x y z Index 0 1 2 ……… 23 24 25
Array2* Element c e m ……… z f g Index 0 1 2 ……… 23 24 25 Random No generated 2 4 12 ……… 25 5 6
* Actual char element allocated to each index location will depend on corresponding random number generated. Program completes execution after filling all 26 locations in Array2.
It seems as though my program is working great but I'm having problems with my random number generator. It keeps giving me a return value from the computer of scissors (or 3) for the computers random choice. What can I do?
//Purpose of Program: This program is meant to prompt the user to choose between 4 menu options. // Each option will be the users choice of rock, paper, or scissors. // the computer will then randomly generate a number and pit you against the computer.
#include <iostream> #include <cstdlib> #include <ctime> using namespace std;
How would I go about creating a random number generator (or pseduorandom I suppose) with user inputted lower and upper bounds along with a user inputted size of the sequence (so they can select how many random numbers they'd like outputted)?
I have to come up with a program that I have to create which is: The Computer guesses a random calculation "Value1 Operator Value2 = Answer." The computer randomly displays two of the four objects. The Player must guess the remaining two objects. If the player gets one right then the computer says "one is right." The game should continue until the user has provided all the correct calculations.
This is what I have, BUT I have 2 errors.
#include "stdafx.h" #include <iostream> #include <cstdlib> #include <ctime> using namespace std; int main() { srand(static_cast<unsigned int>(time(0))); //Random Number Generator double value1 = rand() % 50 + 1; //Random number between 1 and 50
[Code] .....
The errors I am getting in Visual Studio are: error C2181: illegal else without matching if, line 212 IntelliSense: expected a statement, line 212
I am creating a random number generator and have run into a problem with my do while loop. it continually prints one of the lines of output infinitely. what am i missing here?
#include <iostream> #include <cstdlib> #include <ctime> using namespace std; int main() { unsigned seed = time(0);
I've been working on a program on and off for around a week now and I've been struggling towards the end of the program.First of all, the program is a maths quiz which generates two random numbers per question.I'll give you one part of my code:
Code:
srand ( time(NULL) ); //seeds the random number generator int score = 0; int a = rand()%12 +1; //generates a random num between 1-12 int b = rand()%12 +1; int c = a+b; int d; }
[code]....
I've basically copied the above code 10 times and changed the variables by going through the alphabet e.g.
Code:
int a = rand()%12 +1; //generates a random num between 1-12 int b = rand()%12 +1; int c = a+b; int d; all the way to
Code:
int an = rand()%12 +1; int ao = rand()%12 +1; int ap = rand()%12 +1; int aq = an+ao-ap; int ar;
Now what I'm going to do is remove all the declared variables and create a loop. But my problem is; If I wanted to declare four variables for e.g.
Code:
int a = rand()%12 +1; int b = rand()%12 +1; int c = rand()%12 +1; int d = a+b-c;
Would I place the srand( time(NULL)); inside the loop? it's confusing because I know an example of a basic loop with an array would be:
Code:
#include <stdio.h> #include <conio.h> int main(void) {
int test[5]={21,18,47,21,4}; int I; int total=0;
for (I=0;i<5;i++) total += test[I]; }
[code]....
how or where to include the random number generator in the loop and to make it ask 10 questions at random.
I am trying to make a random number generator to simulate a critical hit if the number generated is from 0-critical amount. However, every time i run the code, despite being within the parameters set by the if statements, it always runs through as a critical hit and never a regular hit.
#include <iostream> #include <iomanip> #include <ctime> #include <cstdlib> using namespace std; int main(){ srand((unsigned)time(0));
[Code]...
There are four attempts to save time in getting a good result.
I was running some Monte carlo simulations and I was having some trouble passing my Normal-Random-Generating object as a parameter to the simulator.
I created a class called BoxMull which used the Box-Muller algo to generate Normal randoms and I based the Box-Muller algo on random numbers generated by the Mersenne-twister engine.
I need to create a program that has has an array size of 20 and will generate 20 random numbers in it between 1-1000. Then I need to calculate the average of all the random numbers.
I have half of the code done ,but im lost on how to calculate the average of the random numbers.
Here what I have:
#include <iostream> using namespace std; int i; int size[20]; int counter = 0; int main() { cout << "The Array Consists Of 20 Random Numbers: "<<endl<<endl;
I want to program a program that produces a random number between 1-10, then if the number is correct, says like HEY GOOD JOB and if its not says try AGAIN! also, at any point the user can quit by typing in X.
I know that I can use stuff like cout << "Hey put in a guess now" to prompt the user but I dont know how to accept inputs.
For example, how do I use scanf to do this?
I know that if I use scanf, it takes in a value, but where the heck does it store it?
eg. scanf(%s,guess);
Is that valid? I get an invalid expression error when trying to use that in C++.
-the number of problems they want to do -the type of problem (addition, subtraction, multiplication, division) -the range of numbers for the problems (like 0 to 9, -100 to 100, etc.) [random numbers in the range]
Your program will then display the given number of problems and get the answer from the user. It will tell the user it they are correct or not. If they are incorrect, it will print the correct answer.
After the given number of problems are displayed, the program will give the user the final number correct and percentage correct. The user will be asked if they want to go again. If so, you will reprompt the user for all the information and run again.
I came up with code thinking I was going in the right direction but it doesn't work correctly at all. We have to use functions. My main issue is how do i call variables from another function so all of the functions work together. I repeat I don't understand parameters and calling functions. here's the code:
#include <iostream> #include <cstdlib> #include <iomanip> using namespace std; int get_user_range(int &x, int &y); int get_random_number ();
I'm trying to create a program that creates random numbers. I looked through some examples and this is what I came up with. The time identifier seems to be undefined yet I see no reason it is undefined.
Code: #include "stdafx.h" #include <iostream> using namespace std; int main() { //Re-seed the random-number generator time_t now;
[code]...
here's my error code..
1>------ Build started: Project: bake, Configuration: Debug Win32 ------ 1> bake.cpp 1>c:usersjonbecherdocumentsvisual studio 2012projectsakeakeake.cpp(8): error C3861: 'time': identifier not found 1>c:usersjonbecherdocumentsvisual studio 2012projectsakeakeake.cpp(9): warning C4244: 'argument' : conversion from 'time_t' to 'unsigned int', possible loss of data ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========
