func migratoryBirds(arr []int32) int32 {
    var m map[int32]int32 = make(map[int32]int32)
    for i := range arr {
        el := arr[i]
        _, ok := m[el]
        if !ok {
            m[el] = 0
        } else {
            continue
        }
        
        for j := range arr {
            if el == arr[j] {
                m[el] += 1
            }
        }
    }
    
    var mostFrequentlyId int32
    var current int32
    for k, o := range m {
        if o > current {
            mostFrequentlyId = k
            current = o
        }     
        
        if o == current && k < mostFrequentlyId {
            mostFrequentlyId = k
        }
    }
    
    return mostFrequentlyId
}