結果
| 問題 | No.1976 Cut then Connect |
| ユーザー |
 woodywoody
|
| 提出日時 | 2022-06-12 18:28:43 |
| 言語 | C++14 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
AC
|
| 実行時間 | 264 ms / 2,000 ms |
| コード長 | 6,127 bytes |
| コンパイル時間 | 3,852 ms |
| コンパイル使用メモリ | 233,436 KB |
| 実行使用メモリ | 58,380 KB |
| 最終ジャッジ日時 | 2024-11-24 12:17:46 |
| 合計ジャッジ時間 | 7,727 ms |
|
ジャッジサーバーID （参考情報） |
judge3 / judge1 |
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| ファイルパターン | 結果 |
|---|---|
| sample | AC * 2 |
| other | AC * 31 |
ソースコード
#include<bits/stdc++.h>#include<atcoder/all>#define rep(i,b) for(int i=0;i<b;i++)#define rrep(i,b) for(int i=b-1;i>=0;i--)#define rep1(i,b) for(int i=1;i<b;i++)#define repx(i,x,b) for(int i=x;i<b;i++)#define fore(i,a) for(auto i:a)#define fore1(i,a) for(auto &i:a)#define rng(x) (x).begin(), (x).end()#define rrng(x) (x).rbegin(), (x).rend()#define sz(x) ((int)(x).size())#define pb push_back#define fi first#define se secondusing namespace std;using namespace atcoder;using ll = long long;template<typename T> using mpq = priority_queue<T, vector<T>, greater<T>>;template<typename T> bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }template<typename T> bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }template<typename T> ll sumv(const vector<T>&a){ll res(0);for(auto&&x:a)res+=x;return res;}bool yn(bool a) { if(a) {cout << "Yes" << endl; return 1;} else {cout << "No" << endl; return 0;}}#define dame { cout << "No" << endl; return 0;}#define dame1 { cout << -1 << endl; return 0;}#define test(x) cout << "test" << x << endl;#define deb(x,y) cout << x << " " << y << endl;#define deb3(x,y,z) cout << x << " " << y << " " << z << endl;#define deb4(x,y,z,x2) cout << x << " " << y << " " << z << " " << x2 << endl;#define out cout << ans << endl;#define outv fore(yans , ans) cout << yans << "\n";#define show(x) cerr<<#x<<" = "<<x<<endl;#define showv(v) {fore(vy , v) {cout << vy << " ";} cout << endl;}#define showv2(v) fore(vy , v) cout << vy << "\n";using pll = pair<ll,ll>;using pil = pair<int,ll>;using pli = pair<ll,int>;using pii = pair<int,int>;using tp = tuple<int ,int ,int>;using vi = vector<int>;using vl = vector<ll>;using vs = vector<string>;using vb = vector<bool>;using vpii = vector<pii>;using vpli = vector<pli>;using vpll = vector<pll>;using vpil = vector<pil>;using vvi = vector<vector<int>>;using vvl = vector<vector<ll>>;using vvs = vector<vector<string>>;using vvb = vector<vector<bool>>;using vvpii = vector<vector<pii>>;using vvpli = vector<vector<pli>>;using vvpll = vector<vpll>;using vvpil = vector<vpil>;using mint = modint998244353;using vm = vector<mint>;using vvm = vector<vector<mint>>;vector<int> dx={1,0,-1,0,1,1,-1,-1},dy={0,1,0,-1,1,-1,1,-1};ll gcd(ll a, ll b) { return a?gcd(b%a,a):b;}ll lcm(ll a, ll b) { return a/gcd(a,b)*b;}const double eps = 1e-10;const ll LINF = 1001002003004005006ll;const int INF = 1001001001;vvi e;int n;vvi v1,v2;vvi dia;void dfs(int x,int pre,int cnt){int f=-1,s=-1;int d=0;int cnt_tmp = -1;fore(y , e[x]){cnt_tmp++;if(y == pre) continue;dfs(y , x , cnt_tmp);if (f <= v1[x][cnt_tmp]){chmax(s , f);chmax(f , v1[x][cnt_tmp]);}else{chmax(s , v1[x][cnt_tmp]);if (v2[x][cnt_tmp]) chmax(s , v2[x][cnt_tmp]);}chmax(d , dia[x][cnt_tmp]);}if(pre != -1){v1[pre][cnt] = f+1;v2[pre][cnt] = s+1;dia[pre][cnt] = max(d , f+s+2);}return;}vvi sum1,sum1r;vvi sum2,sum2r;vvi sumd,sumdr;vi prei;void dfs2(int x,int pre,int cnt){rep(i , sz(e[x])) if (e[x][i] == pre) prei[x] = i;int f=0,s=0,d=0;if (pre != -1){if (cnt != 0){chmax(f , sum1[pre][cnt-1]);if (sum2[pre][cnt-1]) chmax(s , sum2[pre][cnt-1]);if (sumd[pre][cnt-1]) chmax(d , sumd[pre][cnt-1]);}if (cnt != sz(v1[pre])-1 ){chmax(f , sum1r[pre][cnt+1]);if (sum2r[pre][cnt+1]) chmax(s , sum2r[pre][cnt+1]);if (sumdr[pre][cnt+1]) chmax(d , sumdr[pre][cnt+1]);}if (0 < cnt && cnt < sz(v1[pre]) -1){chmax(s , min(sum1[pre][cnt-1] , sum1r[pre][cnt+1]));}// if (x == 1){// show(s);// show(cnt);// show(sum2r[pre][cnt+1]);// }v1[x][prei[x]] = f;v2[x][prei[x]] = s;dia[x][prei[x]] = max(d , f+s);}f = -1;s = -1;d = 0;rep(i,sz(e[x])){if (f < v1[x][i]){chmax(s , f);chmax(f , v1[x][i]);}else{chmax(s , v1[x][i]);}// chmax(s , v2[x][i]);chmax(d , dia[x][i]);sum1[x][i] = f+1;sum2[x][i] = s+1;sumd[x][i] = d;// show(x);// show(sum2[x][i]);// show(v2[x][i]);}f = -1;s = -1;d = 0;rrep(i,sz(e[x])){if (f < v1[x][i]){chmax(s , f);chmax(f , v1[x][i]);}else{chmax(s , v1[x][i]);}// chmax(s , v2[x][i]);chmax(d , dia[x][i]);sum1r[x][i] = f+1;sum2r[x][i] = s+1;sumdr[x][i] = d;}rep(i,sz(e[x])){int y = e[x][i];if (y == pre) continue;dfs2(y , x , i);}return;}ll ans = LINF;void dfs_ans(int x,int pre){rep(i,sz(e[x])){int y = e[x][i];if (y == pre) continue;ll dx = dia[x][i];ll dy = dia[y][prei[y]];ll tmp = max({dx , dy , (dx+1)/2+(dy+1)/2 + 1});chmin(ans , tmp);dfs_ans(y , x);}return;}int main(){cin>>n;e.resize(n);v1.resize(n);v2.resize(n);dia.resize(n);sum1.resize(n);sum1r.resize(n);sum2.resize(n);sum2r.resize(n);sumd.resize(n);sumdr.resize(n);prei.resize(n);rep(i,n-1){int a,b; cin>>a>>b;a--; b--;e[a].pb(b);e[b].pb(a);}rep(i,n){int k = sz(e[i]);v1[i].resize(k);v2[i].resize(k);dia[i].resize(k);sum1[i].resize(k);sum2[i].resize(k);sumd[i].resize(k);sum1r[i].resize(k);sum2r[i].resize(k);sumdr[i].resize(k);}dfs(0 , -1 , 0);dfs2(0 , -1 , 0);dfs_ans(0 , -1);// rep(i,n){// int k = sz(e[i]);// rep(j,k) deb3(i,j,sum1[i][j]);// }out;return 0;}