BZOJ1598: [Usaco2008 Mar] Cow Run

Transmission Door

K Short Circuit, the general algorithm is the use of Astar solution, first set up the reverse side run again Dij, or SPFA something. The distance from the opposite edge can be seen as $h () $ in the valuation function. Set $dist$ for the current distance, then $f (node) =dist+h (son) $, and then run Astar, according to some inexplicable things can get the first $i$ out of the stack is the first $i$ short circuit.

Bzoj 1598//by cydiater//2016.10.25#include <iostream> #include <cstring> #include <cstdlib># Include <cstdio> #include <queue> #include <map> #include <ctime> #include <cmath># Include <bitset> #include <string> #include <algorithm> #include <iomanip>using namespace std;# Define ll long long#define up (i,j,n) for (int. i=j;i<=n;i++) #define DOWN (i,j,n) for (int i=j;i>=n;i--) #define PII pair <int,int> #define MP Make_pair#define Pii priority_queue<pii,vector<pii>,greater<pii> >const int maxn=1e6+5;const int Oo=0x3f3f3f3f;inline int read () {char ch=getchar (); int x=0,f=1;while (ch> ' 9 ' | | ch< ' 0 ') {if (ch== '-') F=-1;ch=getchar ();} while (ch>= ' 0 ' &&ch<= ' 9 ') {x=x*10+ch-' 0 '; Ch=getchar ();} return x*f;} int N,m,k,link[maxn],undis[maxn],len=0,f[maxn],cnt[maxn],ans[maxn],dis[maxn];bool vis[MAXN];struct Edge{int y,next , V;} E[MAXN]; Pii q,q;namespace solution{inline void Insert (int x,int Y,int v) {E[++len].next=liNK[X]; Link[x]=len;e[len].y=y;e[len].v=v;} void Init () {n=read (); M=read (); K=read (); up (i,1,m) {int x=read (), Y=read (), V=read (); Insert (x,y,v); insert (Y,X,-V);}} void Pre_dijkstra () {memset (vis,0,sizeof (Vis)); Memset (Undis,10,sizeof (Undis)); undis[1]=0; Q.push (MP (undis[1],1)); Q.empty ()) {PII tmp=q.top (); Q.pop (); int node=tmp.second;if (Vis[node]) continue;vis[node]=1;for (int i=link[node];i;i=e[i].next) if (undis[e[i].y ]>undis[node]-e[i].v&&e[i].v<0) {undis[e[i].y]=undis[node]-e[i].v; Q.push (MP (UNDIS[E[I].Y],E[I].Y));}}} void Now_astar () {memset (cnt,0,sizeof (CNT)), memset (ans,-1,sizeof (ans)), Q.push (MP (Undis[n],n)), while (!q.empty ()) { PII tmp=q.top (); Q.pop (); int node=tmp.second;cnt[node]++;if (node==1) ans[cnt[node]]=tmp.first;for (int i=LINK[node]; I;i=e[i].next) if (cnt[node]<=k&&e[i].v>0) Q.push (MP (tmp.first-undis[node]+e[i].v+undis[e[i].y],e[i ].Y));}} void Slove () {Pre_dijkstra (); Now_astar ();} void output () {Up (i,1,k) printf ("%d\n", Ans[i]);}} int main () {//freopen ("input.in", "R", stdin); using namespace Solution;init (); slove (); output (); return 0;} 

BZOJ1598: [Usaco2008 Mar] Cow run