leetcode-go/leetcode/easy/217.contains-duplicate.go

func containsDuplicate(nums []int) bool {
	set := make(map[int]struct{})
	for i := range nums {
		if _, ok := set[nums[i]]; ok {
			return true
		} else {
			set[nums[i]] = struct{}{}
		}
	}
	return false
}