#include #include #include #include #include #include #include #include #include #include #include #include #define vll vector #define vvvl vector #define vvl vector> #define VV(a, b, c, d) vector>(a, vector(b, c)) #define VVV(a, b, c, d) vector(a, vvl(b, vll (c, d))); #define re(c, b) for(ll c=0;c> a >> b; a += b; ll ans = 0; set st; ll n;std::cin >> n; for(int i=0;i> t; if(st.find(t)!=st.end()) ans += a; st.insert(t); } std::cout << ans << '\n'; }