Check out example codes for "c++ how to generate a random number in a range". It will help you in understanding the concepts better.

Code Example 1

v1 = rand() % 100;         // v1 in the range 0 to 99
v2 = rand() % 100 + 1;     // v2 in the range 1 to 100
v3 = rand() % 30 + 1985;   // v3 in the range 1985-2014

Code Example 2

min + ( std::rand() % ( max - min + 1 ) )

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