POJ 3259 Wormholes
作者：互联网
题目链接：https://vjudge.net/problem/POJ-3259
题目大意
略。分析
Bellman-Ford 判断负环模板题。代码如下
1 #include <cmath>
2 #include <ctime>
3 #include <iostream>
4 #include <string>
5 #include <vector>
6 #include <cstdio>
7 #include <cstdlib>
8 #include <cstring>
9 #include <queue>
10 #include <map>
11 #include <set>
12 #include <algorithm>
13 #include <cctype>
14 #include <stack>
15 #include <deque>
16 #include <list>
17 #include <sstream>
18 #include <cassert>
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,0x7f,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<typename T1, typename T2>
52 istream &operator>>(istream &in, pair<T1, T2> &p) {
53 in >> p.first >> p.second;
54 return in;
55 }
56
57 template<typename T>
58 istream &operator>>(istream &in, vector<T> &v) {
59 for (auto &x: v)
60 in >> x;
61 return in;
62 }
63
64 template<typename T1, typename T2>
65 ostream &operator<<(ostream &out, const std::pair<T1, T2> &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<class T>
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 <= max
100 template<typename T>
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 = 1e9 + 7;
140 const int maxN = 5e2 + 7;
141 const LL ONE = 1;
142 const LL evenBits = 0xaaaaaaaaaaaaaaaa;
143 const LL oddBits = 0x5555555555555555;
144
145 struct Edge{
146 // u->v
147 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, W;
156
157 VI V[maxN];
158 int dist[maxN];
159 vector< Edge > E;
160
161 inline void addEdge(Edge &x) {
162 V[x.u].PB(E.size());
163 E.PB(x);
164 }
165
166 bool Bellman_Ford() {
167 Rep(i, N - 1) {
168 bool flag = 0;
169 Rep(j, E.size()) {
170 // 松弛
171 dist[E[j].v] = min(dist[E[j].v], dist[E[j].u] + E[j].w);
172 flag = 1;
173 }
174 if(!flag) return false; // 提前不能松弛，则可提前退出
175 }
176
177 Rep(j, E.size()) {
178 // 如果还可以松弛，就说明有负环
179 if(dist[E[j].v] > dist[E[j].u] + E[j].w) return true;
180 }
181 return false;
182 }
183
184 void init() {
185 For(i, 1, N) V[i].clear();
186 E.clear();
187 msI(dist);
188 dist[1] = 0; // 目的是查找负环，所以从哪个节点开始都没问题
189 }
190
191 int main(){
192 //freopen("MyOutput.txt","w",stdout);
193 //freopen("input.txt","r",stdin);
194 INIT();
195 cin >> T;
196 while(T--) {
197 cin >> N >> M >> W;
198 init();
199 Rep(i, M) {
200 Edge t;
201 cin >> t;
202 addEdge(t);
203 swap(t.u, t.v);
204 addEdge(t);
205 }
206 Rep(i, W) {
207 Edge t;
208 cin >> t;
209 t.w = -t.w;
210 addEdge(t);
211 }
212
213 if(Bellman_Ford()) cout << "YES\n";
214 else cout << "NO\n";
215 }
216 return 0;
217 }
View Code
标签：3259,typedef,const,map,int,LL,POJ,Wormholes,include 来源： https://www.cnblogs.com/zaq19970105/p/11287260.html