Dijkstra（模板）

  1 #define IOS ios_base::sync_with_stdio(0); cin.tie(0);
  2 #include <cstdio>//sprintf islower isupper
  3 #include <cstdlib>//malloc  exit strcat itoa system("cls")
  4 #include <iostream>//pair
  5 #include <fstream>//freopen("C:\Users\13606\Desktop\草稿.txt","r",stdin);
  6 #include <bitset>
  7 //#include <map>
  8 //#include<unordered_map>  https://www.luogu.org/problem/P4779
  9 #include <vector>
 10 #include <stack>
 11 #include <set>
 12 #include <string.h>//strstr substr
 13 #include <string>
 14 #include <time.h>//srand(((unsigned)time(NULL))); Seed n=rand()%10 - 0~9;
 15 #include <cmath>
 16 #include <deque>
 17 #include <queue>//priority_queue<int, vector<int>, greater<int> > q;//less
 18 #include <vector>//emplace_back
 19 //#include <math.h>
 20 //#include <windows.h>//reverse(a,a+len);// ~ ! ~ ! floor
 21 #include <algorithm>//sort + unique : sz=unique(b+1,b+n+1)-(b+1);+nth_element(first, nth, last, compare)
 22 using namespace std;//next_permutation(a+1,a+1+n);//prev_permutation
 23 //******************
 24 int abss(int a);
 25 int lowbit(int n);
 26 int Del_bit_1(int n);
 27 int maxx(int a,int b);
 28 int minn(int a,int b);
 29 double fabss(double a);
 30 void swapp(int &a,int &b);
 31 clock_t __STRAT,__END;
 32 double __TOTALTIME;
 33 void _MS(){__STRAT=clock();}
 34 void _ME(){__END=clock();__TOTALTIME=(double)(__END-__STRAT)/CLOCKS_PER_SEC;cout<<"Time: "<<__TOTALTIME<<" s"<<endl;}
 35 //***********************
 36 #define rint register int
 37 #define fo(a,b,c) for(rint a=b;a<=c;++a)
 38 #define fr(a,b,c) for(rint a=b;a>=c;--a)
 39 #define mem(a,b) memset(a,b,sizeof(a))
 40 #define pr printf
 41 #define sc scanf
 42 #define ls rt<<1
 43 #define rs rt<<1|1
 44 typedef long long ll;
 45 const double E=2.718281828;
 46 const double PI=acos(-1.0);
 47 const ll INF=(1LL<<60);
 48 const int inf=(1<<30);
 49 const double ESP=1e-9;
 50 const int mod=(int)1e9+7;
 51 const int N=(int)1e6+10;
 52 
 53 struct EDGE
 54 {
 55     int to,next;
 56     ll dis;
 57 }edge[N];
 58 struct node
 59 {
 60     int pos;
 61     ll dis;
 62     friend bool operator<(node a,node b)
 63     {
 64         return a.dis>b.dis;//priority_queue倒着排;
 65     }
 66 };
 67 int tot;
 68 int head[N];
 69 ll dis[N];
 70 bool vis[N];
 71 
 72 void Init(int n)
 73 {
 74     for(int i=1;i<=n;++i)
 75         dis[i]=INF;
 76 }
 77 void add(int from,int to,ll cost)
 78 {
 79     ++tot;
 80     edge[tot].to=to;
 81     edge[tot].dis=cost;    //添加新的点
 82     edge[tot].next=head[from];    //tot代表第几条边
 83     head[from]=tot;    //head指向最新的点(第几条边)
 84 }
 85 priority_queue<node> q;
 86 void Dijkstra(int s)
 87 {
 88     dis[s] = 0;
 89     q.push({s,0});
 90     while( !q.empty() )
 91     {
 92         node tmp = q.top();
 93         q.pop();
 94         int x = tmp.pos;//, d = tmp.dis;
 95         if( vis[x] )
 96             continue;
 97         vis[x] = 1;
 98         for( int i = head[x]; i; i = edge[i].next )
 99         {
100             int y = edge[i].to;
101             if( dis[y] > dis[x] + edge[i].dis )
102             {
103                 dis[y] = dis[x] + edge[i].dis;
104                 if( !vis[y] )
105                 {
106                     q.push({y,dis[y]});
107                 }
108             }
109         }
110     }
111 }
112 
113 int main()
114 {
115 //    freopen("D:\Chrome Download\testdata (4).in","r",stdin);
116     int n,m,start;
117     sc("%d%d%d",&n,&m,&start);
118     Init(n);
119     for(int i=1;i<=m;++i)
120     {
121         int u,v;
122         ll d;
123         sc("%d%d%lld",&u,&v,&d);
124         add(u,v,d);
125     }
126     Dijkstra(start);
127     for(int i=1;i<=n;++i)
128         pr("%lld ",dis[i]);
129     return 0;
130 }
131 
132 /**************************************************************************************/
133 
134 int maxx(int a,int b)
135 {
136     return a>b?a:b;
137 }
138 
139 void swapp(int &a,int &b)
140 {
141     a^=b^=a^=b;
142 }
143 
144 int lowbit(int n)
145 {
146     return n&(-n);
147 }
148 
149 int Del_bit_1(int n)
150 {
151     return n&(n-1);
152 }
153 
154 int abss(int a)
155 {
156     return a>0?a:-a;
157 }
158 
159 double fabss(double a)
160 {
161     return a>0?a:-a;
162 }
163 
164 int minn(int a,int b)
165 {
166     return a<b?a:b;
167 }