11_arrays.nula

// 11_arrays.nula - Array literals, indexing, and manipulation
// Demonstrates: array creation, element access, mutation,
//               array-based algorithms with mutable state
//
// Run: nulang examples/11_arrays.nula

// Array literals and indexing
let primes = [2, 3, 5, 7, 11]
perform IO.print("primes[0] = " + perform Int.to_string(primes[0]))
perform IO.print("primes[2] = " + perform Int.to_string(primes[2]))
perform IO.print("primes[4] = " + perform Int.to_string(primes[4]))

// Iterate with for loop
perform IO.print("All primes:")
for p in primes {
    perform IO.print("  " + perform Int.to_string(p))
}

// Sum array with while loop (using array for mutable counter and total)
let sum_array = fn(arr, n) {
    let st = [0, 0]
    while st[0] < n {
        st[1] = st[1] + arr[st[0]]
        st[0] = st[0] + 1
    }
    st[1]
}
perform IO.print("Sum of primes: " + perform Int.to_string(sum_array(primes, 5)))

// Find max in array
let find_max = fn(arr, n) {
    let st = [1, arr[0]]
    while st[0] < n {
        if arr[st[0]] > st[1] then st[1] = arr[st[0]] else unit
        st[0] = st[0] + 1
    }
    st[1]
}
let nums = [42, 17, 93, 8, 56]
perform IO.print("Max of [42,17,93,8,56]: " + perform Int.to_string(find_max(nums, 5)))

// Array element mutation
let mutable_nums = [1, 2, 3, 4, 5]
mutable_nums[0] = 99
perform IO.print("After [0]=99: " + perform Int.to_string(mutable_nums[0]))

// Array of strings
let names = ["Alice", "Bob", "Carol"]
perform IO.print("Second name: " + names[1])

// Boolean array
let flags = [true, false, true]
perform IO.print("flags[0] = " + perform Int.to_string(if flags[0] then 1 else 0))
perform IO.print("flags[1] = " + perform Int.to_string(if flags[1] then 1 else 0))

// Build squares array
let squares = [0, 0, 0, 0, 0]
let si = [0]
while si[0] < 5 {
    squares[si[0]] = si[0] * si[0]
    si[0] = si[0] + 1
}
perform IO.print("Squares: " + perform Int.to_string(squares[0]) + "," + perform Int.to_string(squares[1]) + "," + perform Int.to_string(squares[2]) + "," + perform Int.to_string(squares[3]) + "," + perform Int.to_string(squares[4]))