From 17f9ae81d28b3de157dd3057fa3a3e2e34c9665c Mon Sep 17 00:00:00 2001 From: oncsr Date: Tue, 14 Oct 2025 12:36:41 +0900 Subject: [PATCH] =?UTF-8?q?[20251014]=20BOJ=20/=20P2=20/=20=ED=86=B5?= =?UTF-8?q?=ED=96=89=EB=9F=89=20=EC=A1=B0=EC=82=AC=20/=20=EA=B6=8C?= =?UTF-8?q?=ED=98=81=EC=A4=80?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- ...1\353\237\211 \354\241\260\354\202\254.md" | 99 +++++++++++++++++++ 1 file changed, 99 insertions(+) create mode 100644 "khj20006/202510/14 BOJ P2 \355\206\265\355\226\211\353\237\211 \354\241\260\354\202\254.md" diff --git "a/khj20006/202510/14 BOJ P2 \355\206\265\355\226\211\353\237\211 \354\241\260\354\202\254.md" "b/khj20006/202510/14 BOJ P2 \355\206\265\355\226\211\353\237\211 \354\241\260\354\202\254.md" new file mode 100644 index 00000000..c3180579 --- /dev/null +++ "b/khj20006/202510/14 BOJ P2 \355\206\265\355\226\211\353\237\211 \354\241\260\354\202\254.md" @@ -0,0 +1,99 @@ +```cpp +#include +using namespace std; + +int N, M, cycCount = 0, E, R, r[200001]{}, ans[200001]{}, dep[200001]{}, s[200001]{}, par[200001][18]{}, cyc[200001][18]{}; +vector>> v(200001); + +int f(int x) {return x==r[x] ? x : r[x]=f(r[x]);} + +int fillCycle(int n, int p, int t) { + if(n == t) return cyc[n][0] = 1; + for(auto [i,_]:v[n]) if(i != p) { + cyc[n][0] |= fillCycle(i,n,t); + } + return cyc[n][0]; +} + +void dfs(int n, int p, int d) { + par[n][0] = p, dep[n] = d; + for(auto [i,_]:v[n]) if(i != p) dfs(i,n,d+1); +} + +int cle(int n, int p) { + for(auto [i,g]:v[n]) if(i != p) { + s[n] += cle(i,n); + if(cyc[i][0]) ans[g] += cycCount; + ans[g] += s[i]; + } + return s[n]; +} + +int main(){ + cin.tie(0)->sync_with_stdio(0); + + cin>>N>>M; + iota(r, r+N+1, 0); + for(int i=0,a,b;i>a>>b; + int x = f(a), y = f(b); + if(x == y) { + fillCycle(a,0,b); + E = i; + R = a; + } + else { + v[a].emplace_back(b,i); + v[b].emplace_back(a,i); + r[x] = y; + } + } + + dfs(R,0,0); + for(int k=1;k<18;k++) for(int i=1;i<=N;i++) { + par[i][k] = par[par[i][k-1]][k-1]; + cyc[i][k] = cyc[i][k-1] + cyc[par[i][k-1]][k-1]; + } + + for(int x,y,c;M--;) { + cin>>x>>y>>c; + int a = x, b = y; + int cycSum = 0, diff = abs(dep[a]-dep[b]); + for(int k=0;k<18;k++) if(diff & (1<=0;k--) if(par[a][k] != par[b][k]) { + cycSum += cyc[a][k] + cyc[b][k]; + a = par[a][k], b = par[b][k]; + } + if(a != b) { + cycSum += cyc[a][0] + cyc[b][0]; + a = par[a][0], b = par[b][0]; + } + int lca = a; + cycSum += cyc[lca][0]; + + s[x] += c; + s[y] += c; + if(cycSum > 1) { + cycCount += c; + for(int k=17;k>=0;k--) { + if(!cyc[x][k]) x = par[x][k]; + if(!cyc[y][k]) y = par[y][k]; + } + s[x] -= c; + s[y] -= c; + } + else { + s[lca] -= 2*c; + } + + } + cle(R,0); + ans[E] += cycCount; + for(int i=0;i