CPP

c++ rand()

#include <iostream>
#include <cstdlib>  //required for rand(), srand()
#include <ctime>    //required for time()
using namespace std;

int main() {
    srand(time(0));     //randomizing results... (using time as an input)
    
    const int totalNumbersGenerated = 30;
    const int minRange = 1, maxRange = 20;

    cout<<"
Printing "<<totalNumbersGenerated<<" random integer numbers (from "<<minRange<<" to "<<maxRange<<"):
";
    
    for(int i=1;i<=totalNumbersGenerated;i++){
        //generating random number in specified range (inclusive)
        cout<<1+((rand () % maxRange) + minRange - 1)<<" ";
    }
    
    cout<<endl;
    return 0;
}

rand c++

#include <iostream>
#include <time.h>

using namespace std;

int main()
{
   srand(time(0));             
   cout<<rand()%100<<endl;            //choose random numbers from 0 to 99
   
   //create random integer value in range a to a+b  (a+rand()b;)
   cout <<1+ rand() % 9 <<endl;   //random numbers between 1 and 10
   cout << 25+rand() % 25 <<endl;   //random numbers between 25 and 50

}

rand() c++

v1 = rand() % 100;         // v1 in the range 0 to 99  --Credit goes to Clever cowfish
v2 = rand() % 100 + 1;     // v2 in the range 1 to 100
v3 = rand() % 30 + 1985;   // v3 in the range 1985-2014

rand() c++

/* rand example */
#include <stdio.h>      /* printf, scanf, puts, NULL */
#include <stdlib.h>     /* srand, rand */
#include <time.h>       /* time */
/* initialize random seed: */
srand (time(NULL));
/* generate  number between 1 and 10: */
random_number = rand() % 10 + 1;

rand function c++

// C++ program to generate random numbers
#include <cstdlib>
#include <iostream>
#include <time.h>
using namespace std;
  
int main()
{
    // This program will create different sequence of
    // random numbers on every program run
  
    // Use current time as seed for random generator
    srand(time(0));
  
    for (int i = 0; i < 4; i++)
        cout << rand() << " ";
  
    return 0;
}

rand() c++

version1 = std::rand() % 3; // it is in the range from 0 to 2 // 0 1 2
version2 = std::rand() % 5 + 2; // it is in the range from 2 to 6 // 2 3 4 5 6
version3 = std::rand() % 3 + 10; // it is in the range from 10 to 12
//first number is how much digits it will go second number is the digit it 
//starts on (including that digit)

//negative
version4 = std::rand() % 11 - 12; // it is in the range from -2 to -12

rand() and srand() in C/C++

rand() function is used in C/C++ to generate random numbers in the range
[0, RAND_MAX). 

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) were called at program start.
Any other value for seed sets the generator to a different starting point.