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# Generating random number in a range in C

• Difficulty Level : Easy
• Last Updated : 24 Aug, 2022

How to generate a random number in a given range in C. Examples:

```Input : Lower = 50,
Upper = 100,
Count of random Number = 5
Output : 91 34 21 88 29
Explanation: lower is the lower limit of the
range and upper is the upper limit of the range.
Output contains 5 random numbers in given range.```

C does not have an inbuilt function for generating a number in the range, but it does have rand function which generates a random number from 0 to RAND_MAX. With the help of rand () a number in range can be generated as num = (rand() % (upper – lower + 1)) + lower

## C

 `// C program for generating a``// random number in a given range.``#include ``#include ``#include ` `// Generates and prints 'count' random``// numbers in range [lower, upper].``void` `printRandoms(``int` `lower, ``int` `upper,``                            ``int` `count)``{``    ``int` `i;``    ``for` `(i = 0; i < count; i++) {``        ``int` `num = (``rand``() %``        ``(upper - lower + 1)) + lower;``        ``printf``(``"%d "``, num);``    ``}``}` `// Driver code``int` `main()``{``    ``int` `lower = 5, upper = 7, count = 1;` `    ``// Use current time as``    ``// seed for random generator``    ``srand``(``time``(0));` `    ``printRandoms(lower, upper, count);` `    ``return` `0;``}`

Output:

`7`

Time complexity: O(N) where N is the count of random numbers to be generated

Auxiliary Space: O(1)

Note: Output generated on each run may be different because the number is generated randomly.

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