Codeforces Round #689 (Div. 2, based on Zed Code Competition) B. Find the Spruce
- Time : O(nm^2)
- Space : O(m)
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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 202020 #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 vi vector<int> #define vs vector<string> #define usll unordered_set<ll> #define uspll unordered_set<pll, PairHash> #define umll unordered_map<ll,ll> #define vvs vector<vs> #define vvll vector<vll> #define all(a) begin(a), end(a) #define rall(a) rbegin(a), rend(a)
using namespace std; ll solve(vs& A) { ll res = 0, m = A[0].size(); vll dp(m); for(auto& r : A) { for(ll i = 0; i < m; i++) { if(r[i] == '.') dp[i] = 0; else dp[i] += 1; } for(ll i = 0; i < m; i++) { ll now = min({dp[i], i + 1, m - i}); for(ll j = 0; j < now; j++) { if(dp[i + j] >= (now - j) and dp[i - j] >= (now - j)) continue; now = min(dp[i + j], dp[i - j]) + j; } res += now; } } return res; }
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,m; cin>>n>>m; vs A(n); for(ll j = 0; j < n; j++) cin>>A[j]; cout<<solve(A)<<endl; } return 0; }
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