【HDOJ】1914 The Stable Marriage Problem

稳定婚姻问题，Gale-Shapley算法可解。

 /* 1914 */
 #include <iostream>
 #include <sstream>
 #include <string>
 #include <map>
 #include <queue>
 #include <set>
 #include <stack>
 #include <vector>
 #include <deque>
 #include <algorithm>
 #include <cstdio>
 #include <cmath>
 #include <ctime>
 #include <cstring>
 #include <climits>
 #include <cctype>
 #include <cassert>
 #include <functional>
 #include <iterator>
 #include <iomanip>
 using namespace std;
 //#pragma comment(linker,"/STACK:102400000,1024000")

 #define sti                set<int>
 #define stpii            set<pair<int, int> >
 #define mpii            map<int,int>
 #define vi                vector<int>
 #define pii                pair<int,int>
 #define vpii            vector<pair<int,int> >
 #define rep(i, a, n)     for (int i=a;i<n;++i)
 #define per(i, a, n)     for (int i=n-1;i>=a;--i)
 #define clr                clear
 #define pb                 push_back
 #define mp                 make_pair
 #define fir                first
 #define sec                second
 #define all(x)             (x).begin(),(x).end()
 #define SZ(x)             ((int)(x).size())
 #define lson            l, mid, rt<<1
 #define rson            mid+1, r, rt<<1|1

 const int maxn = ;
 char s[];
 char wname[];
 int pref[maxn][maxn];
 int order[maxn][maxn];
 int nxt[maxn];
 int future_husband[maxn];
 int future_wife[maxn];
 queue<int> Q;
 int n;
 int ID[];

 void engage(int man, int woman) {
     int m = future_husband[woman];

     if (m) {
         future_wife[m] = ;
         Q.push(m);
     }

     future_husband[woman] = man;
     future_wife[man] = woman;
 }

 void solve() {
     while (!Q.empty()) {
         int man = Q.front();
         Q.pop();
         int woman = pref[man][nxt[man]++];
         if (!future_husband[woman]) {
             engage(man, woman);
         } else if (order[woman][man] < order[woman][future_husband[woman]]) {
             engage(man, woman);
         } else {
             Q.push(man);
         }
     }

     rep(i, 'a', 'z'+) {
         if (!ID[i])
             continue;
         printf("%c %c\n", i, wname[future_wife[ID[i]]]);
     }
 }

 int main() {
     ios::sync_with_stdio(false);
     #ifndef ONLINE_JUDGE
         freopen("data.in", "r", stdin);
         freopen("data.out", "w", stdout);
     #endif

     int t;
     int nlc, nuc;

     scanf("%d", &t);
     while (t--) {
         scanf("%d", &n);
         memset(ID, , sizeof(ID));
         nlc = nuc = ;
         rep(i, , n+n) {
             scanf("%s", s);
             if (islower(s[])) {
                 ID[s[]] = ++nlc;
             } else {
                 ID[s[]] = ++nuc;
                 wname[nuc] = s[];
             }
         }

         while (!Q.empty())
             Q.pop();

         int lid, uid;

         rep(i, , n) {
             scanf("%s", s);
             lid = ID[s[]];
             rep(j, , n+) {
                 uid = ID[s[+j]];
                 pref[lid][j] = uid;
             }
             nxt[lid] = ;
             future_wife[lid] = ;
             Q.push(lid);
         }

         rep(i, , n) {
             scanf("%s", s);
             uid = ID[s[]];
             rep(j, , n+) {
                 lid = ID[s[+j]];
                 order[uid][lid] = j;
             }
             future_husband[uid] = ;
         }
         solve();
         if (t)
             putchar('\n');
     }

     #ifndef ONLINE_JUDGE
         printf("time = %d.\n", (int)clock());
     #endif

     return ;
 }