C++ How To Generate Random Numbers
Random Number
You can use the rand() function, found in the
<cstdlib> library, to generate a random number:
To get more control over the random number, for example, if you only want a random number between 0 and 100, you can use the following formula:
Example
// Generate a random number between 0 and 100
int
randomNum = rand() % 101;
cout << randomNum;
return 0;
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Note: The examples above just outputs a random number once.
They don't output different random numbers each time the program runs. To fix
this, you can use the srand() function
and add the time() function from the <ctime> library.
This will generate a random number from 0 to 100 each time the program runs:
Example
// Get a different random number each time the program runs
srand(time(0));
// Generate a random number between 0 and 100
int
randomNum = rand() % 101;
cout << randomNum;
return 0;
Try it Yourself »
