Map Ok-Idiom

Correct two mistakes in line A and B. 

  1. package main
  3. func main() {
  4.     var m map[string]int //A
  5.     m["a"] = 1
  6.     if v := m["b"]; v != nil { //B
  7.         println(v)
  8.     }
  9. }

Answer

  2. package main
  4. func main() {
  5.     m := make(map[string]int)
  6.     m["a"] = 1
  7.     if v, ok := m["b"]; ok {
  8.         println(v)
  9.     }
  10. }
  12.