[Leetcode] array-Duplicate exists

Given an array of integers, determine if there are duplicate elements.

If any value occurs at least two times in the array, the function returns True. Returns False if each element in the array is not the same.

C++

classSolution { Public:    BOOLContainsduplicate (vector<int>&nums) {Unordered_map<int,int>m;  for(inti =0; I < nums.size (); i++) {            if(M.find (nums[i])! =m.end ())return true; ++M[nums[i]]; }        return false; }};

C

 bool  containsduplicate (int  * nums, Span style= "COLOR: #0000ff" >int   Numssize) { int      I, J;  for  (i = 0 ; i<numssize; I++ for  (j = i +  1 ; j<numssize; J++ if  (Nums[i] == Nums[j])  return          True  ; }}  return  false  ;}  

[Leetcode] array-Duplicate exists