C++ How To Generate Random Numbers
Random Number
You can use the rand()
function, found in the <cstlib>
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 output 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;
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