URAL 10,991-like picture with Flower tree matching

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Test instructions: Give n individuals and many relationships, ask to be able to match the number of people and match the person

Thought: Is said to be with the flower tree template problem, to practice a practice, the principle of what is not the weak can understand, right when it is a template directly with forget, like the maximum flow, and according to the weak to do some of the weak problems found this problem test is the ability to build the map, that is, all the template on the top almost won't And then directly build the map on the line, plainly is too weak to understand the principle of direct when the template made

#include <queue> #include <vector> #include <stdio.h> #include <string.h> #include <stdlib.h > #include <iostream> #include <algorithm>using namespace std;typedef long long ll;typedef unsigned long Long Ull;const int inf=0x3f3f3f3f;const ll inf=0x3f3f3f3f3f3f3fll;const int Maxn=230;int f[maxn],spouse[maxn],next[ Maxn],q[maxn],mark[maxn],vis[maxn];int n,bot;vector<int>g[maxn];int find1 (int x) {if (x!=f[x]) f[x]=find1 (F[x]    ); return f[x];}    void Unite (int a,int b) {int aa=find1 (a);    int Bb=find1 (b);    if (AA==BB) return; F[AA]=BB;}    int Findlca (int x,int y) {static int t=0;    t++;            while (1) {if (x!=-1) {x=find1 (x);            if (vis[x]==t) return x;            vis[x]=t;            if (spouse[x]!=-1) x=next[spouse[x]];        else X=-1;    } swap (x, y);        }}void goup (int a,int p) {while (a!=p) {int b=spouse[a],c=next[b];        if (Find1 (c)!=p) next[c]=b; if (mark[b]==2) mark[q[bot++]=b]=1;        if (mark[c]==2) mark[q[bot++]=c]=1;    Unite (A, b); Unite (b,c); a=c;    }}void findaugment (int s) {for (int i=0;i<n;i++) next[i]=-1,f[i]=i,mark[i]=0,vis[i]=-1;    Q[0]=s;bot=1;mark[s]=1;        for (int head=0;spouse[s]==-1&&head<bot;head++) {int x=q[head];            for (unsigned int i=0;i<g[x].size (); i++) {int y=g[x][i]; if (Spouse[x]!=y&&find1 (x)!=find1 (y) &&mark[y]!=2) {if (mark[y]==1) {int p=                    Findlca (x, y);                    if (Find1 (x)!=p) next[x]=y;                    if (Find1 (y)!=p) next[y]=x;                Goup (x,p); Goup (y,p);                    }else if (spouse[y]==-1) {next[y]=x;                        for (int j=y;j!=-1;) {int k=next[j];                        int l=spouse[k];                    Spouse[j]=k;spouse[k]=j;j=l;                } break;                    }else{next[y]=x; MaRk[q[bot++]=spouse[y]]=1;                mark[y]=2;    }}}}}int Num[maxn][maxn];int main () {scanf ("%d", &n);    int x, y;    for (int i=0;i<n;i++) {for (int j=0;j<n;j++) num[i][j]=0;        } while (scanf ("%d%d", &x,&y)!=eof) {x--;y--;            if (x!=y&&num[x][y]==0) {num[x][y]=num[y][x]=1;            G[x].push_back (y);        G[y].push_back (x);    }} for (int i=0;i<n;i++) spouse[i]=-1;    for (int i=0;i<n;i++) {if (spouse[i]==-1) findaugment (i);    } int ans=0;    for (int i=0;i<n;i++) if (spouse[i]!=-1) ans++;    printf ("%d\n", ans);    for (int i=0;i<n;i++) {if (spouse[i]!=-1&&spouse[i]>i) printf ("%d%d\n", i+1,spouse[i]+1); } return 0;}

URAL 10,991-like picture with Flower tree matching