random number generator

[mitaka12102]

Can someone help me with my c++ homework:Make a c++ code that prints 1 random number from 5 to 20.

I tried stuff like:

#include "stdafx.h"
#include <iostream>
#include <cstdlib>
#include <ctime>
using namespace std;

int _tmain(int argc, _TCHAR* argv[])
{

srand(time(NULL));
for(int i=1; i<31; i++)
{
cout<<rand() % 60 <<" ";
if(i % 10 == 0)
cout<<endl;
}


system("pause");
return 0;
}

and

#include <stdlib.h>
#include <stdio.h>
#include <time.h>

/* function main begins program execution */
int main(void) {
	int i;

	srand(time(NULL));
	for (i = 1; i <= 1; i++) {

		/* pick a random number from 1 to 6 and output it */
		printf("%10d", 1 + (rand() % 2));

		/* if counter is divisible by 5, begin a new line of output */
		if (i % 5 == 0) {
			printf("\n");
		} /* end if */
	} /* end for */

	return 0; /* indicates successful termination */
} /* end main */

but none of them work.

[syedfahadjalali]

if you want to store a random number from 5 to 20

int temp;
temp = rand()%21;
while(temp == 0 || temp == 1 || temp == 2 || temp == 3 || temp == 4)
{
temp = rand()%21;
}
cout<<temp; // the number will be from 5 to 20

[mitaka12102]

Yea it prints me "20"

[syedfahadjalali]

it will always give you result from 5 to 20

[mitaka12102]

I need a code that changes this number

[cire]

#include <cstdlib>
#include <ctime>
#include <iostream>

unsigned getRandom( unsigned min, unsigned max )
{
    unsigned range = max-min+1 ;

    return rand() % range + min ;
}

int main()
{
    std::srand(std::time(0)) ;

    unsigned nRandomNums ;
    unsigned minimum ;
    unsigned maximum ;

    std::cout << "Number of random numbers to generate: " ;
    std::cin >> nRandomNums ;

    std::cout << "Minimum: " ;
    std::cin >> minimum ;

    std::cout << "Maximum: " ;
    std::cin >> maximum ;

    for ( unsigned i=0; i<nRandomNums; ++i )
        std::cout << '\t' << getRandom(minimum, maximum) << '\n' ;
}

[mitaka12102]

Cool but now I have a new problem:
I shouldn't use std::
I deleted some parts of the code and now it looks like this:

#include <cstdlib>
#include <ctime>
#include <iostream>

long long getRandom( long long min, long long max )
{
    long long range = max-min+1 ;

    return rand() % range + min ;
}

int main()
{
    std::srand(std::time(0)) ;

    long long nRandomNums ;
    long long minimum=5 ;
    long long maximum=20 ;

    std::cout << "count of random numbers: " ;
    std::cin >> nRandomNums ;
    for ( long long i=0; i<nRandomNums; ++i )
    std::cout << getRandom(minimum, maximum) << "\n" ;
}

when I try it without it the only problems are at

std::cout << "Maximum: " ;
std::cin >> maximum ;

and

std::cout << '\t' << getRandom(minimum, maximum) << '\n' ;
where I have two errors:

...|20|error: 'cout' was not declared in this scope|

and

...|21|error: 'cin' was not declared in this scope|

Can someone tell me how to fix this error?