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1 #include 2 #include 3 #include 4 #include 5 #include 6 #include 7 #include 8 #include 9 #include 10 #include 11 #include 12 #include 13 #include 14 #include 15 #include 16 #include 17 #include 18 #include 19 using namespace std; 20 21 #define INIT() ios::sync_with_stdio(false);cin.tie(0);cout.tie(0); 22 #define Rep(i,n) for (int i = 0; i < (n); ++i) 23 #define For(i,s,t) for (int i = (s); i <= (t); ++i) 24 #define rFor(i,t,s) for (int i = (t); i >= (s); --i) 25 #define ForLL(i, s, t) for (LL i = LL(s); i <= LL(t); ++i) 26 #define rForLL(i, t, s) for (LL i = LL(t); i >= LL(s); --i) 27 #define foreach(i,c) for (__typeof(c.begin()) i = c.begin(); i != c.end(); ++i) 28 #define rforeach(i,c) for (__typeof(c.rbegin()) i = c.rbegin(); i != c.rend(); ++i) 29 30 #define pr(x) cout << #x << " = " << x << " " 31 #define prln(x) cout << #x << " = " << x << endl 32 33 #define LOWBIT(x) ((x)&(-x)) 34 35 #define ALL(x) x.begin(),x.end() 36 #define INS(x) inserter(x,x.begin()) 37 #define UNIQUE(x) x.erase(unique(x.begin(), x.end()), x.end()) 38 #define REMOVE(x, c) x.erase(remove(x.begin(), x.end(), c), x.end()); // 删去 x 中所有 c 39 #define TOLOWER(x) transform(x.begin(), x.end(), x.begin(),::tolower); 40 #define TOUPPER(x) transform(x.begin(), x.end(), x.begin(),::toupper); 41 42 #define ms0(a) memset(a,0,sizeof(a)) 43 #define msI(a) memset(a,inf,sizeof(a)) 44 #define msM(a) memset(a,-1,sizeof(a)) 45 46 #define MP make_pair 47 #define PB push_back 48 #define ft first 49 #define sd second 50 51 template 52 istream &operator>>(istream &in, pair &p) { 53 in >> p.first >> p.second; 54 return in; 55 } 56 57 template 58 istream &operator>>(istream &in, vector &v) { 59 for (auto &x: v) 60 in >> x; 61 return in; 62 } 63 64 template 65 ostream &operator<<(ostream &out, const std::pair &p) { 66 out << "[" << p.first << ", " << p.second << "]" << "\n"; 67 return out; 68 } 69 70 inline int gc(){ 71 static const int BUF = 1e7; 72 static char buf[BUF], *bg = buf + BUF, *ed = bg; 73 74 if(bg == ed) fread(bg = buf, 1, BUF, stdin); 75 return *bg++; 76 } 77 78 inline int ri(){ 79 int x = 0, f = 1, c = gc(); 80 for(; c<48||c>57; f = c=='-'?-1:f, c=gc()); 81 for(; c>47&&c<58; x = x*10 + c - 48, c=gc()); 82 return x*f; 83 } 84 85 template 86 inline string toString(T x) { 87 ostringstream sout; 88 sout << x; 89 return sout.str(); 90 } 91 92 inline int toInt(string s) { 93 int v; 94 istringstream sin(s); 95 sin >> v; 96 return v; 97 } 98 99 //min <= aim <= max100 template 101 inline bool BETWEEN(const T aim, const T min, const T max) {102 return min <= aim && aim <= max;103 }104 105 typedef long long LL;106 typedef unsigned long long uLL;107 typedef pair< double, double > PDD;108 typedef pair< int, int > PII;109 typedef pair< int, PII > PIPII;110 typedef pair< string, int > PSI;111 typedef pair< int, PSI > PIPSI;112 typedef set< int > SI;113 typedef set< PII > SPII;114 typedef vector< int > VI;115 typedef vector< double > VD;116 typedef vector< VI > VVI;117 typedef vector< SI > VSI;118 typedef vector< PII > VPII;119 typedef map< int, int > MII;120 typedef map< LL, int > MLLI;121 typedef map< int, string > MIS;122 typedef map< int, PII > MIPII;123 typedef map< PII, int > MPIII;124 typedef map< string, int > MSI;125 typedef map< string, string > MSS;126 typedef map< PII, string > MPIIS;127 typedef map< PII, PII > MPIIPII;128 typedef multimap< int, int > MMII;129 typedef multimap< string, int > MMSI;130 //typedef unordered_map< int, int > uMII;131 typedef pair< LL, LL > PLL;132 typedef vector< LL > VL;133 typedef vector< VL > VVL;134 typedef priority_queue< int > PQIMax;135 typedef priority_queue< int, VI, greater< int > > PQIMin;136 const double EPS = 1e-8;137 const LL inf = 0x3fffffff;138 const LL infLL = 0x3fffffffffffffffLL;139 const LL mod = 20100713;140 const int maxN = 1e3 + 7;141 const LL ONE = 1;142 const LL evenBits = 0xaaaaaaaaaaaaaaaa;143 const LL oddBits = 0x5555555555555555;144 145 struct Edge{146 // u->v147 int u, v, w;148 }; 149 150 istream& operator>> (istream &in, Edge &x) {151 in >> x.u >> x.v >> x.w;152 return in;153 }154 155 int T, N, M; 156 157 VI V[maxN];158 int maxW[maxN];159 vector< Edge > E;160 bool vis[maxN];161 162 inline void addEdge(Edge &x) {163 V[x.u].PB(E.size());164 E.PB(x);165 }166 167 void init() {168 For(i, 1, N) V[i].clear();169 ms0(maxW);170 E.clear();171 172 ms0(vis);173 }174 175 void Dijkstra() {176 priority_queue< PII > Q; // 大顶堆 177 Q.push(MP(inf, 1));178 maxW[1] = inf;179 180 while(!Q.empty()) {181 PII tmp = Q.top(); Q.pop();182 if(vis[tmp.sd]) continue;183 vis[tmp.sd] = 1;184 if(tmp.sd == N) return;185 186 Rep(i, V[tmp.sd].size()) {187 Edge &e = E[V[tmp.sd][i]];188 if(vis[e.v]) continue;189 190 if(min(maxW[tmp.sd], e.w) > maxW[e.v]) {191 maxW[e.v] = min(maxW[tmp.sd], e.w);192 Q.push(MP(maxW[e.v], e.v));193 }194 } 195 }196 }197 198 int main(){199 //freopen("MyOutput.txt","w",stdout);200 //freopen("input.txt","r",stdin);201 INIT();202 cin >> T;203 For(cases, 1, T) {204 cin >> N >> M;205 init();206 Rep(i, M) {207 Edge t;208 cin >> t;209 addEdge(t);210 swap(t.u, t.v);211 addEdge(t);212 }213 214 Dijkstra();215 216 cout << "Scenario #" << cases << ":\n";217 cout << maxW[N] << "\n\n";218 }219 return 0;220 }
转载于:https://www.cnblogs.com/zaq19970105/p/11275878.html
