// compound assignment operators: +=, -=, *=, /=

fn main() {
    let x = 10
    println(x)
    
    x += 5
    println(x)      // 15
    
    x -= 3
    println(x)      // 12
    
    x *= 2
    println(x)      // 24
    
    x /= 4
    println(x)      // 6
    
    // compound assignment on arrays (field access for structs/maps)
    let m = { "count": 0 }
    m["count"] += 1
    println(m["count"])    // 1
    
    m["count"] += 10
    println(m["count"])    // 11
    
    // compound assignment on array index
    let arr = [10, 20, 30]
    arr[1] += 5
    println(arr[1])        // 25
    
    arr[2] *= 3
    println(arr[2])        // 90
}