package main
import (
"fmt"
"math/rand"
"sort"
"time"
)
/*
This program generates random lottery numbers for:
- 6 distinct numbers out of 37
- 1 distinct number out of 7 (power number)
It uses:
- math/rand with time-based seeding
- rand.Shuffle() for efficient unique selection
- clean functions and idiomatic Go style
*/
/*
pickDistinctNumbers(count, max):
Generates 'count' distinct random numbers from the range [1..max].
Algorithm:
- Create a slice containing all numbers 1..max
- Shuffle the slice using rand.Shuffle()
- Take the first 'count' numbers
This guarantees:
- all numbers are unique
- uniform randomness
- no duplicate checks needed
*/
func pickDistinctNumbers(count, max int) []int {
numbers := make([]int, max)
for i := 0; i < max; i++ {
numbers[i] = i + 1
}
rand.Shuffle(len(numbers), func(i, j int) {
numbers[i], numbers[j] = numbers[j], numbers[i]
})
return numbers[:count]
}
/*
pickPowerNumber(max):
Returns a single random number in the range [1..max].
*/
func pickPowerNumber(max int) int {
return rand.Intn(max) + 1
}
func main() {
rand.Seed(time.Now().UnixNano()) // Seed RNG
mainCount := 6
mainMax := 37
powerMax := 7
// Generate main numbers (distinct)
mainNumbers := pickDistinctNumbers(mainCount, mainMax)
sort.Ints(mainNumbers) // sort for nicer output
// Generate power number
powerNumber := pickPowerNumber(powerMax)
// Output results
fmt.Printf("Main numbers (6 out of 37): %v\n", mainNumbers)
fmt.Printf("Power number (1 out of 7): %d\n", powerNumber)
}
/*
run:
Main numbers (6 out of 37): [10 13 19 22 26 34]
Power number (1 out of 7): 4
*/
