UVa/12319 - Edgetown's Traffic Jams/12319.cpp

   1 // Equipo Poncho, Carriel y Ruana
   2 using namespace std;
   3 #include <algorithm>
   4 #include <iostream>
   5 #include <iterator>
   6 #include <sstream>
   7 #include <fstream>
   8 #include <cassert>
   9 #include <climits>
  10 #include <cstdlib>
  11 #include <cstring>
  12 #include <string>
  13 #include <cstdio>
  14 #include <vector>
  15 #include <cmath>
  16 #include <queue>
  17 #include <stack>
  18 #include <list>
  19 #include <map>
  20 #include <set>
  21
  22 template <class T> string toStr(const T &x)
  23 { stringstream s; s << x; return s.str(); }
  24 template <class T> int toInt(const T &x)
  25 { stringstream s; s << x; int r; s >> r; return r; }
  26
  27 #define For(i, a, b) for (int i=(a); i<(b); ++i)
  28 #define foreach(x, v) for (typeof (v).begin() x = (v).begin(); x != (v).end(); ++x)
  29 #define D(x) cout << #x " = " << (x) << endl;
  30
  31 const double EPS = 1e-9;
  32
  33 int cmp(double x, double y = 0, double tol = EPS) {
  34     return (x <= y + tol) ? (x + tol < y) ? -1 : 0 : 1;
  35 }
  36
  37 const int MAXN = 105;
  38 const int oo = 1<<28;
  39
  40 int g1[MAXN][MAXN];
  41 int g2[MAXN][MAXN];
  42 int n;
  43
  44 vector<int> gg1[MAXN], gg2[MAXN];
  45
  46 int dist[MAXN];
  47 void bfs(int start, vector<int> g[MAXN]) {
  48     For(i, 0, n) dist[i] = oo;
  49     queue<int> q;
  50     dist[start] = 0;
  51     q.push(start);
  52     while (q.size()) {
  53         int u = q.front();
  54         q.pop();
  55
  56         for (int k = 0; k < g[u].size(); ++k) {
  57             int v = g[u][k];
  58
  59             if (dist[v] < oo) continue;
  60             dist[v] = dist[u] + 1;
  61             q.push(v);
  62         }
  63     }
  64 }
  65
  66 bool equal(long long a, long long b) {
  67     For(i, 0, n) {
  68         For(j, 0, n) {
  69             if (g2[i][j] >= oo) return false;
  70             long long now = g2[i][j];
  71             long long cota = g1[i][j] * a + b;
  72             if (now > cota) {
  73                 //printf("From %d to %d: now = %d, cota = %d, old = %d\n", i, j, (int)now, (int)cota, g1[i][j]);
  74                 return false;
  75             }
  76         }
  77     }
  78     return true;
  79 }
  80
  81 int main(){
  82     while (cin >> n) {
  83         if (n == 0) break;
  84         string s; getline(cin, s);
  85
  86         For (i, 0, n) For(j, 0, n) g1[i][j] = g2[i][j] = oo;
  87         For (i, 0, n) gg1[i].clear(), gg2[i].clear();
  88
  89         for (int i = 0; i < n; ++i) {
  90             getline(cin, s);
  91             stringstream sin(s);
  92             int first; sin >> first; first--;
  93             int other;
  94             while (sin >> other) {
  95                 other--;
  96                 g1[first][other] = 1;
  97                 gg1[first].push_back(other);
  98             }
  99         }
 100
 101         for (int i = 0; i < n; ++i) {
 102             getline(cin, s);
 103             stringstream sin(s);
 104             int first; sin >> first; first--;
 105             int other;
 106             while (sin >> other) {
 107                 other--;
 108                 g2[first][other] = 1;
 109                 gg2[first].push_back(other);
 110             }
 111         }
 112         For(i, 0, n) g1[i][i] = g2[i][i] = 0;
 113
 114         int a, b;
 115         cin >> a >> b;
 116         if (a == 0 and b == 0 and n > 1) {
 117             puts("No");
 118             continue;
 119         }
 120
 121         //puts("G1"); For(i, 0, n){  For(j, 0, n) { printf("%10d", g1[i][j]); } puts(""); } puts("");
 122         //puts("G2"); For(i, 0, n){  For(j, 0, n) { printf("%10d", g2[i][j]); } puts(""); } puts("");
 123
 124         //floyd();
 125
 126         For(i, 0, n) {
 127             bfs(i, gg1);
 128             For(j, 0, n) {
 129                 g1[i][j] = dist[j];
 130             }
 131             bfs(i, gg2);
 132             For(j, 0, n) {
 133                 g2[i][j] = dist[j];
 134             }
 135         }
 136
 137         if (equal(a, b)) {
 138             puts("Yes");
 139         } else {
 140             puts("No");
 141         }
 142     }
 143     return 0;
 144
 145 }