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| #include <stdio.h> #include <string.h> #include <vector> #include <iostream> #include <set> #include <map> #include <queue> #define ll long long #define clr(a,b) memset(a,b,sizeof(a)) using namespace std;
const int N = 105;
const int inf = 1e8; int g[N][N],a[N][N],p[N]; bool vis[N],combine[N],par[N]; int d[N],node[N],st[N],k,s,t; vector<int> vst[N]; vector<int> pa,pb;
int prim(int n){ clr(vis,0); clr(d,0); int mincut = 0; int tmp = -1; s =-1, t =-1; int top = 0; for(int i=0;i<k;i++){ int maxi = -inf; for(int j=0;j<k;j++){ int u = node[j]; if(!combine[u]&&!vis[u]&&d[u]>maxi){ tmp = u; maxi = d[u]; } } st[top++] = tmp; vis[tmp] = true; if(i==k-1) mincut=d[tmp]; for(int j=0;j<k;j++){ int u=node[j]; if(!combine[u]&&!vis[u]) d[u] += g[tmp][u]; } } s = st[top-2]; t = st[top-1]; for(int i=0;i<top;i++) node[i] = st[i]; return mincut; } int Stoer_Wagner(int n){ for(int i=0;i<n;i++){ vst[i].clear(); vst[i].push_back(i); }
int ans = inf; clr(combine,0); for(int i=0;i<n;i++) node[i] = i; for(int i=1;i<n;i++){ k = n-i+1; int cur = prim(n); if(cur<ans){ ans =cur; for(int j=0;j<n;j++) par[j] = 0; for(int j=0;j<vst[t].size();j++){ par[vst[t][j]] = 1; }
} combine[t] = true;
for(int j=0;j<vst[t].size();j++){ vst[s].push_back(vst[t][j]); } for(int j=0;j<n;j++){ if(j==s) continue; if(!combine[j]){ g[s][j] += g[t][j]; g[j][s] += g[j][t]; } } } pa.clear();pb.clear(); for(int i=0;i<n;i++) if(par[i]) pa.push_back(i); else pb.push_back(i); return ans; }
int K;
int dfs(vector<int> t){ int n = t.size(); for(int i=0;i<n;i++) for(int j=0;j<n;j++) g[i][j] = a[t[i]][t[j]]; if(Stoer_Wagner(n)>=K) return 1; vector<int> x,y; for(int i=0;i<pa.size();i++) x.push_back(t[pa[i]]); for(int i=0;i<pb.size();i++) y.push_back(t[pb[i]]); return dfs(x) + dfs(y); } int main(){ // freopen("/home/zyc/Documents/Code/cpp/in","r",stdin); int n,m; while(scanf("%d%d%d",&n,&m,&K)!=EOF){ clr(a,0); for(int i=0;i<m;i++){ int u,v; scanf("%d%d",&u,&v); u--;v--; a[u][v] += 1; a[v][u] += 1; } vector<int> t; for(int i=0;i<n;i++) t.push_back(i); printf("%d\n",dfs(t)); } return 0; }
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