#include<bits/stdc++.h>
typedef long long ll;
#define pb push_back
#define fr first
#define sc second
#define endl '\n'
using namespace std;
#define mid ((left+right)>>1)
int n;
int table[2023][2023];
signed main(){
ios_base::sync_with_stdio(23^23);cin.tie(0);
cin>>n;
for(int i=1;i<=n;i++){
for(int j=i;j<=n;j++){
cin>>table[i][j];
}
}
int l=1,r=n;
while(table[l+1][r]==table[l][r])l++;
while(table[l][r-1]==table[l][r])r--;
for(int i=l;i<=r;i++){
if(table[l+1][i-1]!=table[l][i-1]){
if(table[l][i]!=table[l][i-1]){
cout<<i<<" ";
}
continue;
}
if(table[i+1][r-1]!=table[i+1][r]){
if(table[i][r]!=table[i+1][r]){
cout<<i<<" ";
}
continue;
}
if(table[l+1][i-1]!=table[l+1][i])continue;
if(table[i+1][r-1]!=table[i][r-1])continue;
cout<<i<<" ";
}
cout<<endl;
}
