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uva 334

頗有難度的題目
難題幾乎都是考驗變形的功力 已哭

[sourcecode language="cpp"]
//============================================================================
// Name : Identifying Concurrent Events.cpp
// Date : 2013 2013/3/10 下午12:58:37
// Author : GCA
//============================================================================
#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <climits>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <cctype>
#include <utility>
using namespace std;
#ifdef ONLINE_JUDGE
#define ll "%lld"
#else
#define ll "%I64d"
#endif
typedef unsigned int uint;
typedef long long int Int;
#define Set(a,s) memset(a,s,sizeof(a))
#define Write(w) freopen(w,"w",stdout)
#define Read(r) freopen(r,"r",stdin)
#define Pln() printf("\n")
#define I_de(x,n)for(int i=0;i<n;i++)printf("%d ",x[i]);Pln()
#define De(x)printf(#x"%d\n",x)
#define For(i,x)for(int i=0;i<x;i++)
#define CON(x,y) x##y
#define Pmz(dp,nx,ny)for(int hty=0;hty<ny;hty++){for(int htx=0;htx<nx;htx++){\
printf("%d ",dp[htx][hty]);}Pln();}
#define M 100005
#define PII pair<int,int>
#define PB push_back
#define oo INT_MAX
#define Set_oo 0x3f
#define Is_debug true
#define debug(...) if(Is_debug)printf("DEBUG: "),printf(__VA_ARGS__)
#define FOR(it,c) for(__typeof((c).begin()) it=(c).begin();it!=(c).end();it++)
#define eps 1e-6
bool xdy(double x,double y){return x>y+eps;}
bool xddy(double x,double y){return x>y-eps;}
bool xcy(double x,double y){return x<y-eps;}
bool xcdy(double x,double y){return x<y+eps;}
int min3(int x,int y,int z){
int tmp=min(x,y);
return min(tmp,z);
}
int max3(int x,int y,int z){
int tmp=max(x,y);
return max(tmp,z);
}
int n,m;
int mz[500][500];
map<string,int> sid;
map<int,string> rsid;
int main() {
ios_base::sync_with_stdio(0);
int ff=0;
while(~scanf("%d",&n)&&n){
char str1[10],str2[10];
Set(mz,0);
sid.clear();
int knum=0;
for(int i=0;i<n;i++){
vector<string> v;
int tmpn;
char str[10];
scanf("%d",&tmpn);
while(tmpn--){
scanf("%s",str);
v.PB(str);
}
if(sid[v[0]]==0){
rsid[knum]=v[0];
sid[v[0]]=knum++;
}
for(uint i=1;i<v.size();i++){
if(sid[v[i]]==0){
rsid[knum]=v[i];
sid[v[i]]=knum++;
}
mz[sid[v[i-1]]][sid[v[i]]]=1;
}
}
scanf("%d",&m);
for(int i=0;i<m;i++){
scanf("%s%s",str1,str2);
mz[sid[str1]][sid[str2]]=1;
}
for(int k=0;k<knum;k++){
for(int i=0;i<knum;i++){
for(int j=0;j<knum;j++){
mz[i][j]|=mz[i][k]&mz[k][j];
}
}
}
int cnt=0;
char ans[3][3][10];
for(int i=0;i<knum;i++){
for(int j=i+1;j<knum;j++){
if(!(mz[i][j]||mz[j][i])){
if(cnt<2){
sprintf(ans[cnt][0],"%s",rsid[i].c_str());
sprintf(ans[cnt][1],"%s",rsid[j].c_str());

}cnt++;
}
}
}
// for(int i=0;i<knum;i++){
// for(int j=0;j<knum;j++){
// printf("%d ",mz[i][j]);
// }Pln();
// }
if(cnt>=1){
printf("Case %d, %d concurrent events:\n",++ff,cnt);
for(int i=0;i<min(2,cnt);i++){
printf("(%s,%s) ",ans[i][0],ans[i][1]);
}Pln();
}
else printf("Case %d, no concurrent events.\n",++ff);
}

}

[/sourcecode]