#include <bits/stdc++.h>
using namespace std;
using namespace std::chrono;
using ll=long long;
using pll=pair<ll,ll>;
using pq_int=priority_queue<int,vector<int>,greater<int>>;
const ll LINF=0x3fffffffffffffff;
const ll MOD=1000000007;
const ll MODD=0x3b800001;
const int INF=0x3fffffff;
#define _overload4(_1,_2,_3,_4,name,...) name
#define _overload3(_1,_2,_3,name,...) name
#define _rep1(n) _rep2(i,n)
#define _rep2(i,n) _rep3(i,0,n)
#define _rep3(i,a,b) for(ll i=a;i<b;++i)
#define _rep4(i,a,b,c) for(ll i=a;i<b;i+=c)
#define rep(...) _overload4(__VA_ARGS__,_rep4,_rep3,_rep2,_rep1)(__VA_ARGS__)
#define _rrep1(n) _rrep2(i,n)
#define _rrep2(i,n) _rrep3(i,0,n)
#define _rrep3(i,a,b) for(ll i=b-1;i>=a;i--)
#define _rrep4(i,a,b,c) for(ll i=a+(b-a-1)/c*c;i>=a;i-=c)
#define rrep(...) _overload4(__VA_ARGS__,_rrep4,_rrep3,_rrep2,_rrep1)(__VA_ARGS__)
#define each(i,a) for(auto&& i:a)
#define sum(...) accumulate(range(__VA_ARGS__),0)
#define _range(i) (i).begin(),(i).end()
#define _range2(i,k) (i).begin(),(i).begin()+k
#define _range3(i,a,b) (i).begin()+a,(i).begin()+b
#define range(...) _overload3(__VA_ARGS__,_range3,_range2,_range)(__VA_ARGS__)
#define Yes(i) out(i?"Yes":"No")
#define YES(i) out(i?"YES":"NO")
//#define START auto start=system_clock::now()
//#define END auto end=system_clock::now();cerr<<duration_cast<milliseconds>(end-start).count()<<" ms\n"
#define INT(...) int __VA_ARGS__;in(__VA_ARGS__)
#define LL(...) ll __VA_ARGS__;in(__VA_ARGS__)
#define STR(...) string __VA_ARGS__;in(__VA_ARGS__)
#define CHR(...) char __VA_ARGS__;in(__VA_ARGS__)
#define DBL(...) double __VA_ARGS__;in(__VA_ARGS__)
#define vec(type,name,size) vector<type> name(size);
#define VEC(type,name,size) vector<type> name(size);in(name)
#define v(type,name,size,value) vector<type>name(size,value)
#define vv(type,name,h,w,value) vector<vector<type>>name(h,vector<type>(w,value))
__attribute__((constructor)) void SETTINGS(){cin.tie(0); cout.tie(0); ios::sync_with_stdio(0); cout<<fixed<<setprecision(15);};
template<typename T>
inline constexpr T gcd (T a,T b) {if(a==b)return a;else return gcd(b,(a-1)%b+1);}
template<typename T>
T min(vector<T> v){return *min_element(range(v));}
template<typename T>
T max(vector<T> v){return *max_element(range(v));}
inline void in() {}
template<typename T>
istream& operator >> (istream& is, vector<T>& vec);
template<typename T,size_t size>
istream& operator >> (istream& is, array<T,size>& vec);
template<typename T,typename L>
istream& operator >> (istream& is, pair<T,L>& p);
template<typename T>
ostream& operator << (ostream& os, vector<T>& vec);
template<typename T,typename L>
ostream& operator << (ostream& os, pair<T,L>& p);
template<typename T>
istream& operator >> (istream& is, vector<T>& vec){for(T& x: vec) is >> x;return is;}
template<typename T,typename L>
istream& operator >> (istream& is, pair<T,L>& p){is >> p.first;is >> p.second;return is;}
template<typename T>
ostream& operator << (ostream& os, vector<T>& vec){os << vec[0];rep(i,1,vec.size()){os << ' ' << vec[i];}return os;}
template<typename T,typename L>
ostream& operator << (ostream& os, pair<T,L>& p){os << p.first << " " << p.second;return os;}
template <class Head, class... Tail>
inline void in(Head&& head,Tail&&... tail){cin>>head;in(move(tail)...);}
template <typename T>
inline void out(T t){cout<<t<<'\n';}
inline void out(){cout<<'\n';}
template <class Head, class... Tail>
inline void out(Head head,Tail... tail){cout<<head<<' ';out(move(tail)...);}




signed main(){
    INT(n);
    vv(int,a,n,0,0);
    rep(n){
        INT(m);
        rep(j,m){
            INT(k);
            a[i].push_back(k);
        }
    }
    ll ans=0;
    priority_queue<int> q;
    rrep(n){
        each(j,a[i])q.push(j);
        if(!q.empty()){
            ans+=q.top();
            q.pop();
        }
    }
    out(ans);
}










Measured memory_bytes: 19216