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. 1. i. Description of the problem ii. Algorithm of the...

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

1.

i. Description of the problem

ii. Algorithm of the following codes (both methods)

iii. Analyze the running time of each step of the algorithms (both methods)

Method 1:

class Solution {
public:
bool containsDuplicate(vector& nums) {

int n= nums.size();
sort(begin(nums), end(nums));

for (int i=1; i
{
if (nums[i] == nums[i-1])
{
return true;
}
}
return false;
}
};

Method 2:

class Solution {
public:
bool containsDuplicate(vector& nums) {

int n = nums.size();
set s;

for (int i=0; i
{
if (s.count(nums[i]))
{
return true;
}
s.insert(nums[i]);
}
return false;
}
};