217、Contains Duplicate
Given an array of integers, find if the array contains any duplicates.
Your function should return true if any value appears at least twice in the array, and it should return false if every element is distinct.
Example 1:
Input: [1,2,3,1] Output: true
Example 2:
Input: [1,2,3,4] Output: false
思路：
很简单的一题，只用找出数组中有没有重复的数字,用set或者map做就可以。
代码：
java：
代码语言：javascript复制class Solution {
public boolean containsDuplicate(int[] nums) {
return IntStream.of(nums).distinct().count() != nums.length;
}
}go：
代码语言：javascript复制func containsDuplicate(nums []int) bool {
if nums == nil || len(nums) == 0 {return false}
maps := make(map[int]bool)
for _, v := range nums {
if maps[v] {
return true
} else {
maps[v] = true
}
}
return false
}
