30秒学会 Golang 片段 – Frequencies

Returns a map with the unique values of the collection as keys and their frequencies as the values.

Implement an appropriate function for each type.
Use make() to create a map.
Use range to iterate over the elements in the collection, adding to existing keys every time the same value is encountered.

代码实现

func FrequenciesInt(arr []int) map[int]int {
    m := make(map[int]int)
    for _, v := range arr {
        if f, ok := m[v]; ok {
            m[v] = f + 1
        } else {
            m[v] = 1
        }
    }
    return m
}
func FrequenciesFloat64(arr []float64) map[float64]int {
    m := make(map[float64]int)
    for _, v := range arr {
        if f, ok := m[v]; ok {
            m[v] = f + 1
        } else {
            m[v] = 1
        }
    }
    return m
}
func FrequenciesBool(arr []bool) map[bool]int {
    m := make(map[bool]int)
    for _, v := range arr {
        if f, ok := m[v]; ok {
            m[v] = f + 1
        } else {
            m[v] = 1
        }
    }
    return m
}
func FrequenciesString(arr []string) map[string]int {
    m := make(map[string]int)
    for _, v := range arr {
        if f, ok := m[v]; ok {
            m[v] = f + 1
        } else {
            m[v] = 1
        }
    }
    return m
}

使用样例

MySnippet() // "result"