双拓扑排序 HDOJ 5098 Smart Software Installer

 

题目传送门

 1 /*  2  双拓扑排序：抄的，以后来补  3  详细解释：http://blog.csdn.net/u012774187/article/details/40736995  4 */  5 #include <cstdio>  6 #include <algorithm>  7 #include <iostream>  8 #include <sstream>  9 #include <cstring>  10 #include <cmath>  11 #include <string>  12 #include <vector>  13 #include <queue>  14 #include <map>  15 #include <set>  16 #include <ctime>  17 #include <cstdlib>  18 using namespace std;  19  20 #define lson l, mid, rt << 1  21 #define rson mid + 1, r, rt << 1 | 1  22 typedef long long ll;  23  24 const int MAXN = 1e3 + 10;  25 const int INF = 0x3f3f3f3f;  26 const double PI = acos (-1.0);  27 const double EPS = 1e-9;  28 struct Edge  29 {  30 int v, nxt;  31 }e[MAXN * MAXN];  32 int in[MAXN], out[MAXN];  33 int re[MAXN], head[MAXN];  34 bool vis[MAXN];  35 map<string, int> M;  36 vector<int> G[MAXN];  37 int ecnt, cnt;  38  39 int TopoSort(void)  40 {  41 queue<int> Q1, Q2; //Q1 !re Q2 re  42 for (int i=1; i<=cnt; ++i)  43  {  44 if (!in[i])  45  {  46 if (!re[i]) Q1.push (i);  47 else Q2.push (i);  48  }  49  }  50  51 int ans = 0;  52 while (!Q1.empty () || !Q2.empty ())  53  {  54 if (Q1.empty () && !Q2.empty ()) //重启  55  {  56 ans++;  57 while (!Q2.empty ()) //所有都重启安装  58  {  59  Q1.push (Q2.front ()); Q2.pop ();  60  }  61  }  62 while (!Q1.empty ())  63  {  64 int u = Q1.front (); Q1.pop ();  65 vis[u] = true;  66 for (int i=head[u]; i!=-1; i=e[i].nxt)  67  {  68 int v = e[i].v;  69 if (!(--in[v]))  70  {  71 if (!re[v]) Q1.push (v);  72 else Q2.push (v);  73  }  74  }  75  }  76  }  77  78 return ans;  79 }  80  81 void init(void)  82 {  83  M.clear ();  84 ecnt = cnt = 0;  85 memset (in, 0, sizeof (in));  86 memset (out, 0, sizeof (out));  87 memset (re, 0, sizeof (re));  88 memset (head, -1, sizeof (head));  89 memset (vis, false, sizeof (vis));  90 }  91  92 void add_edge(int u, int v)  93 {  94 e[ecnt].nxt = head[u];  95 e[ecnt].v = v;  96 head[u] = ecnt++;  97 }  98  99 int main(void) //HDOJ 5098 Smart Software Installer 100 { 101 //freopen ("I.in", "r", stdin); 102 103 string s; 104 char name[1050]; 105 int n, cas = 0; scanf ("%d", &n); getchar (); getchar (); 106 while (n--) 107  { 108  init (); 109 while (getline (cin, s)) 110  { 111 if (s[0] == '\0') break; 112  istringstream sin (s); 113 sin >> name; 114 int len = strlen (name); int flag = 0; 115 if (name[len-2] == '*') {flag = 1; name[len-2] = '\0';} 116 else name[len-1] = '\0'; 117 118 string u = name, v; 119 if (M.find (u) == M.end ()) 120 M[u] = ++cnt; 121 re[M[u]] = flag; 122 123 while (sin >> v) 124  { 125 if (M.find (v) == M.end ()) 126 M[v] = ++cnt; 127  add_edge (M[v], M[u]); 128 out[M[v]]++; 129 in[M[u]]++; 130  } 131  } 132 printf ("Case %d: %d\n", ++cas, TopoSort ()); 133  } 134 135 return 0; 136 } 137 138 /* 139 Case 1: 1 140 Case 2: 2 141 */