Codeforces Round #778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) C. Alice and the Cake
- Time : O(nlogn)
- Space : O(n)
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| #include <bits/stdc++.h>
#pragma optimization_level 3 #pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math,O3") #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx") #pragma GCC optimize("Ofast") #pragma GCC target("avx,avx2,fma") #pragma GCC optimization ("unroll-loops")
struct PairHash {inline std::size_t operator()(const std::pair<int,int> & v) const {return v.first*31+v.second;}};
#define MAX_N 1010 #define INF 987654321 #define EPS 1e-9 #define ll long long #define pll pair<ll, ll> #define vpll vector<pll> #define vall3 vector<array<ll,3>> #define all3 array<ll,3> #define all5 array<ll,5> #define vall5 vector<all5> #define vll vector<ll> #define vs vector<string> #define usll unordered_set<ll> #define uspll unordered_set<pll, PairHash> #define vvs vector<vs> #define vvll vector<vll> #define all(a) begin(a), end(a)
using namespace std;
string solve(vll& A) { ll sum = accumulate(all(A), 0ll), mi = *min_element(all(A)); unordered_map<ll, ll> freq; for(auto& a : A) freq[a]++; vll st{sum}; while(!freq.empty()) { auto& n = st.back(); st.pop_back(); if(n < mi) return "NO"; if(freq.count(n)) { if(--freq[n] == 0) freq.erase(n); } else { auto a = n / 2, b = n / 2 + (n & 1); st.push_back(b); st.push_back(a); } } return "YES"; }
int main() { ios_base::sync_with_stdio(0); cin.tie(0); ll tc = 1; cin>>tc; for(ll i = 1; i <= tc; i++) { ll n; cin>>n; vll A(n); for(ll i = 0; i < n; i++) cin>>A[i]; cout<<solve(A)<<endl; } return 0; }
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