lavos/cap3/ex13.go

package cap3

type Subject int
type Student int

func Ex14(subjectPassedStudentMap map[Subject]Student) []Student {
	result := make([]Student, 0)

	// 学生及格科目数记录
	studentRecord := map[Student]int{}
	for _, student := range subjectPassedStudentMap {
		// 对当前学生及格科目计数
		if _, exists := studentRecord[student]; !exists {
			studentRecord[student] = 1
		} else {
			studentRecord[student]++
		}

		// 学生及格科目数已达到传入的科目数，即为全科及格
		if studentRecord[student] == len(subjectPassedStudentMap) {
			result = append(result, student)
		}
	}

	return result
}