Given a function rand7 which generates a uniform random integer in the range 1 to 7, write a function rand10which generates a uniform random integer in the range 1 to 10.
Do NOT use system's Math.random().
Example 1:
Input: 1
Output: [7]
Example 2:
Input: 2
Output: [8,4]
Example 3:
Input: 3
Output: [8,1,10]
Note:
- rand7 is predefined.
- Each testcase has one argument:n, the number of times that rand10 is called.
Follow up:
- What is the expected valuefor the number of calls torand7()function?
- Could you minimize the number of calls to rand7()?
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