一個小小工程師的心情抒發天地

Given an integer array nums, return true if any value appears at least twice in the array, and return false if every element is distinct.

Example 1:

Input: nums = [1,2,3,1]
Output: true

Example 2:

Input: nums = [1,2,3,4]
Output: false

Example 3:

Input: nums = [1,1,1,3,3,4,3,2,4,2]
Output: true

Constraints:

• 1 <= nums.length <= 105
• -109 <= nums[i] <= 109

class Solution {
public:
    bool containsDuplicate(vector<int>& nums) {
            map<int, int> CorrespondTable;
    for (auto x : nums)
        CorrespondTable[x]++;
    for (auto y : CorrespondTable) {
        if (y.second > 1) {
            return true;
        }
    }
    return false;
    }
};