Help me in solving CONCUSSIVE problem

help
,
1

My issue

why this solution is not acceptable if answer is validate situation
include <bits/stdc++.h>
using namespace std;

int main() {
int t;
cin>>t;
while(t–){
int n;
cin>>n;
vectorv(n,0);
for(int i=0;i<n;i++)cin>>v[i];
sort(v.begin(),v.end());
vectornums(n,0);
unordered_map<int,int>mp;
bool chk = 0;
for(int i =0,j=0 ;i<n;i++){
mp[v[i]] ++;
if(mp[v[i]]>n/2 + n%2)chk =1;
if(j >=n){
j =1;
}
nums[j] = v[i];
j+=2;
}
if(chk){
cout<<-1;
}else {
for(int i=0;i<n;i++)cout<<nums[i]<<" ";
}
cout<<endl;
}
return 0;
}

My code

#include <bits/stdc++.h>
using namespace std;

int main() {
	int  t;
	cin>>t;
	while(t--){
	    int n;
	    cin>>n;
	    vector<long long >v(n,0);
	    for(int i=0;i<n;i++)cin>>v[i];
	    sort(v.begin(),v.end());
	    vector<long long >nums(n,0);
	    unordered_map<int,int>mp;
	    bool chk = 0;
	    for(int  i =0,j=0 ;i<n;i++){
	        mp[v[i]] ++;
	        if(mp[v[i]]>n/2 + n%2)chk =1;
	        if(j >=n){
	            j =1;
	        }
	        nums[j] = v[i];
	        j+=2;
	    }
	    if(chk){
	        cout<<-1;
	    }else {
	        for(int  i=0;i<n;i++)cout<<nums[i]<<" ";
	    }
	    cout<<endl;
	}
	return 0;
}

Problem Link: CONCUSSIVE Problem - CodeChef