C++ Making Lottery Software

The simplest method is to define a Boolean array a[n], the default value is false (indicating that it has not been taken away), and then generate a random number rd=rand()/(n- 1).

Then look at the values in the array and count them, for example, count with I, and when the values in the element are false, i++, look at the next one. If it's true, look at the next one, and then calculate until i=rd. Change the value of the element you are viewing to true (to prevent it from being drawn a second time) and record the index number in the array. You drew this. As for what you mean, you. . . . Of course, when you count to the end of the array, remember to drop to the beginning. . .